U.S. Route 40
US 40 highlighted in red
Route information
Maintained byMDSHA,Baltimore DOT, andMDTA
Length	221.31 mi[1][2] (356.16 km)
Existed	1926–present
Tourist routes	Historic National Road Journey Through Hallowed Ground Byway Chesapeake and Ohio Canal Scenic Byway Antietam Campaign Scenic Byway
Major junctions
West end	US 40 at thePennsylvania state line
Major intersections	I-68 /US 219 nearGrantsville US 220 inCumberland I-70 /US 522 inHancock I-81 nearHagerstown US 15 /US 340 / Jefferson Street inFrederick I-70 /I-270 in Frederick US 29 inEllicott City I-695 inCatonsville US 1 inBaltimore I-95 in Baltimore
East end	US 40 atDelaware border inElkton
Location
Country	United States
State	Maryland
Counties	Garrett,Allegany,Washington,Frederick,Carroll,Howard,Baltimore,City of Baltimore,Harford,Cecil
Highway system
United States Numbered Highway System List Special Divided Maryland highway system Interstate US State Scenic Byways
←MD 39 →MD 41

U.S. Route 40 (US 40) in theU.S. state ofMaryland runs fromGarrett County inWestern Maryland toCecil County in the state's northeastern corner. With a total length of 221 miles (356 km), it is the longest numbered highway in Maryland. Almost half of the roadoverlaps or parallels withInterstate 68 (I-68) orI-70, while the old alignment is generally known as US 40 Alternate,US 40 Scenic, orMaryland Route 144 (MD 144). West ofBaltimore, in thePiedmont andAppalachian Mountains /Blue Ridge region of the Western Maryland panhandle of the small state, the portions where it does not overlap an Interstate highway are mostly two-lane roads. The portion northeast of Baltimore going towardWilmington in northernDelaware andPhiladelphia in southeasternPennsylvania is a four-lane divided highway, known as the Pulaski Highway (named forAmerican Revolutionary War (1775–1783) foreign military volunteer ofPolish cavalry officerCasimir Pulaski, 1745–1779). This section crosses theSusquehanna River at the north end of theChesapeake Bay on theThomas J. Hatem Memorial Bridge.

FromCumberland on the western branch of thePotomac River and terminus of the historicChesapeake and Ohio Canal, west toPennsylvania, US 40 is the successor to the historic route of theNational Road, first Federal interstate road built in the early 19th century which eventually ran from Baltimore west, throughOhio,Indiana, andIllinois toVandalia, then territorial capital of theIllinois Territory near theMississippi River.

East of Cumberland, towards Baltimore, US 40 follows several former private companyturnpikes, most notably the Cumberland Turnpike,Baltimore and Frederick-town Turnpike, later known as Frederick Road (MD 144) between Baltimore andFrederick.

The route from Baltimore northeast to theDelaware state line follows another historicEast Coast / Northeast Corridor routing towardsPhiladelphia,New York City andBoston including the oldBaltimore and Havre-de-Grace Turnpike (now mostly bypassed and known as the Old Philadelphia Road,MD 7).

US 40 enters Maryland fromPennsylvania inGarrett County and follows a two-lane undivided road toKeysers Ridge. Between Keysers Ridge andHancock, US 40 runsconcurrent withI-68 across the mountains ofWestern Maryland, passing throughCumberland. In Hancock, US 40 becomes concurrent withI-70 and follows thePotomac River before it splits from I-70. US 40 follows a two-lane road parallel to I-70 east toHagerstown, where it passes through thecenter of the city and turns southeast. Between Hagerstown andFrederick, the route heads southeast along a two-lane road parallel to I-70 through rural areas. In Frederick, US 40 joinsUS 15 on afreeway alignment before it continues east concurrent with I-70. US 40 follows I-70 east through rural areas toHoward County, where it splits from I-70 and continues along a multilanedivided highway through suburban areas, passing throughEllicott City.^[1][3] The route heads east through the city ofBaltimore along city streets, with a freeway section located west ofdowntown Baltimore.^[2][3] US 40 continues northeast from Baltimore along Pulaski Highway, a multilane divided highway that runs parallel toI-95 through suburban areas, passing throughAberdeen. BetweenHavre de Grace andPerryville, the route crosses theSusquehanna River on theThomas J. Hatem Memorial Bridge. US 40 continues east parallel to I-95 and leaves Maryland forDelaware inElkton.^[1][3]

Throughout Maryland, US 40 is paralleled by several former alignments that are designated as U.S. or state highways.US 40 Alt. is designated along the former alignment between Keysers Ridge and Cumberland while anotherUS 40 Alt. runs along the former alignment between Hagerstown and Frederick.US 40 Scenic is designated along a former alignment parallel to I-68/US 40 in easternAllegany County and westernWashington County.MD 144 is designated along several separate former alignments between Cumberland and Baltimore whileMD 7 is designated along several separate former alignments between Baltimore and Elkton.^[1][3]

US 40 enters Maryland fromPennsylvania inGarrett County in theWestern Maryland region of the state. From the state line, the route heads southeast onNational Pike, a three-lane undivided road with one eastbound lane and two westbound lanes that soon narrows to a two-lane road as it descends Winding Ridge, which is part of theAllegheny Mountains. The road runs through wooded areas with some farmland and homes, withMD 733C looping to the north. US 40 continues southeast through sections of theSavage River State Forest and has a junction withMD 826H, at which point it curves east and passes businesses as a four-lane undivided road before intersecting the western terminus ofUS 40 Alt. in the community ofKeysers Ridge. At this point, US 40 Alt. continues east along National Pike while US 40 turns south onto a two-lane road and comes to acloverleaf interchange withI-68 andUS 219.^[1][3]

At this interchange, US 219 continues south along the two-lane road while US 40 heads southeastconcurrent with I-68 and US 219 on National Freeway, a four-lanefreeway that has a third lane for trucks while climbing hills and mountains. The road curves east and passes through another section of the Savage River State Forest, heading acrossNegro Mountain. Past the crossing of Negro Mountain, I-68/US 40/US 219 passes through a mix of farmland and woodland, coming to adiamond interchange withMD 495 to the south of the town ofGrantsville. Following this interchange, the freeway descends a hill before it crosses theCasselman River. After crossing the river, the road ascends a hill, running through wooded areas and curving to the east-southeast. US 219 splits from I-68/US 40 by heading north on a freeway at adumbbell interchange; this interchange also marks the southern terminus ofUS 219 Bus. From here, I-68/US 40 continues east-southeast along the National Freeway as it ascends forested Meadow Mountain. At the summit of the mountain, the road reaches an interchange with Lower New Germany Road (MD 948D). Past this interchange, the freeway descends the mountain. I-68/US 40 heads east through a mix of farmland and woodland, ascending and descending two hills and crossing theEastern Continental Divide. Farther east, the freeway curves southeast and comes to an interchange withMD 546 inFinzel. Following this, the road heads across forestedSavage Mountain.^[1][3]

I-68/US 40 crosses intoAllegany County and continues to descend Savage Mountain, coming to an eastboundweigh station. The road curves south and then southeast before it comes to a diamond interchange with Midlothian Road (MD 736) inMidlothian that provides access to the city ofFrostburg andFrostburg State University to the northeast. From here, the freeway turns east as it runs through wooded areas with some nearby development, crossing overGeorges Creek andMD 936 before passing south ofGod's Ark of Safety church and reaching an interchange withMD 36 that serves Frostburg. I-68/US 40 continues east-northeast and descends a hill, passing over Spruce Hollow andMD 55 to the south ofClarysville. The median of the road widens and it heads across forestedDans Mountain, with US 40 Alt. parallel a short distance to the north in the Braddock Run valley. After crossing Dans Mountain, the freeway leaves the Allegheny Mountains. At this point, I-68/US 40 reaches a partial interchange connecting to US 40 Alt. andMD 53 inLa Vale, with a westbound exit and entrance and an eastbound entrance. Following this, the road passes near developed areas and comes to a partial interchange with Vocke Road (MD 658), with all movements except a westbound entrance. At this interchange, southboundUS 220 Truck becomes concurrent with westbound I-68/US 40, splitting to head south along Vocke Road. From here, the freeway turns northeast and ascends forestedHaystack Mountain. The road turns east and reaches the summit of the mountain, where it begins to descend the mountain. I-68/US 40 comes to a westbound ramp with Seton Drive that provides access toMD 49.^[1][3]

Following this, the freeway curves northeast and enters the city ofCumberland, coming to an interchange withUS 220. At this point, US 220 Truck ends and US 220 joins I-68/US 40 on the National Freeway, which descends a 6 percent grade. The road passes south of residential areas of the city, coming to a bridge overCSX'sMountain Subdivision railroad line and Kelly Road, where there is an eastbound entrance from Kelly Road. From here, the freeway runs along the north bank of theNorth Branch Potomac River and curves northeast through developed areas, coming to an eastboundright-in/right-out interchange with Johnson Street and a westbound right-in/right-out interchange with Beall Street that serves Cumberland along withRidgeley, West Virginia across the river. I-68/US 40/US 220 continues east and passes overWills Creek and theWestern Maryland Scenic Railroad south of theCumberland station, heading away from the North Branch Potomac River, before passing over theChesapeake and Ohio Canal and coming to an interchange withMD 51 to the south of downtown Cumberland. Past this interchange, the road passes over CSX'sCumberland Terminal Subdivision railroad line south of theCumberland station servingAmtrak'sCapitol Limited train before it reaches a right-in/right-out interchange serving Maryland Avenue near homes and some businesses. From here, the freeway curves northeast and passes through wooded areas with nearby development before coming to a diamond interchange with the eastern terminus of US 40 Alt. and the western terminus ofMD 639.^[1][3]

I-68/US 40/US 220 continues northeast through forested areas and leaves Cumberland, reaching an interchange with Hillcrest Drive (MD 952). Following this, the road comes to a westbound exit and entrance withMD 144, where it curves east and US 220 splits from I-68/US 40 by heading north at an interchange that also has access to MD 144. Past this interchange, I-68/US 40 ascends a grade as it runs through forested areas with some fields, curving northeast and passing over MD 144. The freeway continues northeast, with MD 144 closely parallel to the southeast, and comes to a diamond interchange with Pleasant Valley Road (MD 948AD) that provides access toRocky Gap State Park to the north. From here, the road ascendsMartin Mountain Ridge and comes to an eastbound exit and westbound entrance with MD 144 at the summit of the ridge. From here, the I-68/US 40 descends the ridge, turning to the southeast and east as it runs through a mix of farmland and woodland closely parallel to MD 144. The freeway reaches an interchange connecting to MD 144 inFlintstone. From here, the road heads acrossPolish Mountain, curving southeast. I-68/US 40 turns east and continues through theGreen Ridge State Forest parallel to MD 144. Farther east, the freeway passes under MD 144 before it comes to an interchange with the western terminus ofUS 40 Scenic at Fifteen Mile Creek Road. Past this interchange, the road turns southeast before it curves east and reaches an interchange with M.V. Smith Road (MD 948AL). I-68/US 40 turns northeast and descends Town Hill. The road heads into wooded areas with some farm fields and curves east to an interchange with Orleans Road (MD 948Z). The freeway continues east as it descends a grade before passing under US 40 Scenic, which begins to parallel the freeway to the south. I-68/US 40 reaches an interchange with High Germany Road (MD 948Y) inBellegrove, where US 40 Scenic joins the freeway. Past this interchange, the road crossesSideling Hill Creek.^[1][3]

Upon crossing Sideling Hill Creek, I-68/US 40 entersWashington County and curves northeast through forested areas, ascending a grade and coming to a westboundrunaway truck ramp. US 40 Scenic splits from the freeway at an eastbound exit and westbound entrance with Mountain Road (MD 903). Past this interchange, I-68/US 40 turns east and passes through a 340-foot (100 m) massive deep cut inSideling Hill, where the freeway curves southeast and begins to descend the hill. Just to the east of the cut is a pair ofrest areas and the Sideling Hill Welcome Center along the westbound side of the road, with a pedestrian bridge providing access from the eastbound direction. Following this, the freeway continues southeast, passing an eastbound runaway truck ramp, before it comes to a diamond interchange with the eastern terminus of US 40 Scenic and the western terminus of a section of MD 144, where it turns northeast. The road curves east and crosses through a gap inTonoloway Ridge as it continues through forested areas with some farm fields. I-68 reaches its eastern terminus at adirectional T interchange withI-70/US 522 near the town ofHancock, where US 40 continues east concurrent with I-70/US 522 on the Eisenhower Memorial Highway, a four-lane freeway. Soon after, US 522 splits from I-70/US 40 at a directional T interchange by heading south and providing access to Hancock. Following this, the freeway continues east across a forested hill, with a third lane for trucks while climbing the hill. The road comes to a westbound exit and eastbound entrance with the eastern terminus of the Hancock section of MD 144, where the median widens and it heads east through wooded areas with theWestern Maryland Rail Trail, Chesapeake and Ohio Canal, and thePotomac River parallel to the south. I-70/US 40 comes to an eastbound exit and westbound entrance withMD 615 before MD 615 closely parallels the road to the north to a westbound exit and eastbound entrance at MD 615's southern terminus. Past this interchange, the freeway curves to the southeast.^[1][3]

US 40 splits from I-70 at an eastbound exit and westbound entrance, where it continues southeast onto two-lane undivided National Pike. The road passes through wooded areas with some fields and homes, curving to the east. In the community ofIndian Springs, the route intersects Big Pool Road, which heads south to an interchange with I-70 and becomesMD 56. US 40 continues east and crosses forested Fairview Mountain, gaining a second eastbound lane as it ascends the mountain and a second westbound lane as it descends the mountain heading northeast. At the summit of Fairview Mountain,MD 739A loops to the south of the route. After crossing the mountain, the road turns east and enters theHagerstown Valley, where it passes farm fields before entering the town ofClear Spring. In Clear Spring, the route becomes Cumberland Street and is lined with homes and some businesses, coming to a junction with the western terminus ofMD 68. After leaving Clear Spring, US 40 becomes National Pike again and runs through agricultural areas with some woods and homes, intersecting the southern terminus ofMD 57. The road continues east through rural areas and crossesConococheague Creek before passing to the south ofHagerstown Speedway. The route runs through a mix of farmland, woodland, and development, crossingMD 63 before intersecting the western terminus of a section of MD 144 and curving northeast.^[1][3]

At this point, US 40 widens to a four-lanedivided highway and turns back to the east, entering the city ofHagerstown. Here, the road passes north of residential areas before heading near businesses and coming to a cloverleaf interchange withI-81. Past this interchange, the route intersects the northern terminus ofMD 910 before it curves southeast and splits into theone-way pair of Washington Avenue eastbound and West Franklin Street westbound, carrying two lanes in each direction. US 40 passes through residential areas before the eastbound direction becomes West Washington Street and the route heads into commercial areas, intersectingUS 11. Past this junction, the one-way pair passes under railroad tracks carrying CSX'sLurgan Subdivision andNorfolk Southern's Hagerstown District lines and enters the commercial downtown of Hagerstown. At the intersection with Potomac Street, the road name changes to East Washington Street eastbound and East Franklin Street westbound. US 40 leaves downtown Hagerstown and the directions of the route rejoin as four-lane divided Dual Highway, intersecting the western terminus ofMD 64 and passing a mix of homes and businesses. The road curves to the south-southeast and crossesAntietam Creek as it continues through developed areas, briefly widening to six lanes as it passes several businesses. At the southeastern edge of Hagerstown, the route reaches a cloverleaf interchange with I-70. Following this interchange, US 40 leaves Hagerstown and becomes National Pike, soon narrowing to a two-lane undivided road and passing through farmland and residential development with some woods. The road comes to an intersection withMD 66 in the community ofBeaver Creek before it heads to the north of Mason-Dixon Dragway and the community ofMount Lena. Farther southeast, the route leaves the Hagerstown Valley as it ascends forestedSouth Mountain, turning south and passing to the east ofGreenbrier State Park. At the summit of the mountain, US 40 curves southeast and crosses over I-70 and theAppalachian Trail.^[1][3]

After crossing over I-70 and the Appalachian Trail, US 40 entersFrederick County and becomes Baltimore National Pike, heading southeast through forested areas to descend South Mountain as it passes to the south ofSouth Mountain State Park. The road continues into theMiddletown Valley and passes through a mix of farmland, woodland, and some residential and commercial development along a straight alignment. The route passes along the northeast border of the town ofMyersville and comes to an intersection withMD 17. From here, US 40 continues southeast through agricultural land with some woods and development. Farther southeast, the road leaves the Middletown Valley and ascends forestedCatoctin Mountain, passing south ofGambrill State Park and north of the community ofArch Bridge. The route passes near some fields and development at the summit before it heads south to descend the forested mountain, with I-70 parallel a short distance to the west. US 40 comes to a westbound exit to westbound I-70 and an eastbound entrance from eastbound I-70, at which point it turns east and becomes a four-lane divided highway. The road enters the city ofFrederick and curves southeast. At this point, the route becomes West Patrick Street and passes businesses, coming to an intersection with the eastern terminus ofUS 40 Alt. US 40 turns back to the east and widens to six lanes, passing south of the formerFrederick Towne Mall as it continues through a commercial strip known as the "Golden Mile" before coming to apartial cloverleaf interchange with theUS 15 freeway. At this interchange, West Patrick Street continues east as a municipal street while US 40 heads south concurrent with US 15 on the four-lane Frederick Freeway. The median of the freeway widens as it passes between office buildings to the west and residential areas to the east. The freeway median narrows again as it curves southeast and comes to a partial cloverleaf interchange with Jefferson Street and the northern terminus ofUS 340, where US 15 splits from US 40 by heading southwest concurrent with US 340. From here, US 40 continues southeast along the Frederick Freeway past commercial development before it comes to an interchange with I-70 and the northern terminus ofI-270.^[1][3]

At this point, the freeway continues southeast as part of I-270 while US 40 heads east to follow I-70 along the Baltimore National Pike, a six-lane freeway. The freeway heads east through business areas and passes south ofNymeo Field at Harry Grove Stadium, the home ballpark of theFrederick Keys baseball team, before crossing underMD 355 and coming to asingle-point urban interchange withMD 85. The road passes over theFrederick Branch of CSX'sOld Main Line Subdivision railroad line before it comes to a partial cloverleaf interchange with South Street and Monocacy Boulevard and a partial interchange with MD 144. Past this interchange, I-70/US 40 passes through fields before it leaves Frederick upon crossing theMonocacy River. The freeway runs near suburban residential development and woodland, curving southeast and coming to a partial interchange with the eastern terminus of the Frederick section of MD 144 inBartonsville, with no eastbound exit. Past this interchange, the road continues east through wooded areas with some fields and development, with Old National Pike parallel a short distance to the north. I-70/US 40 passes south of the town ofNew Market and comes to a diamond interchange withMD 75 that serves the town. The freeway heads east through woodland with some farmland and nearby residential development, with Old National Pike parallel to the north and CSX's Old Main Line Subdivision parallel to the south. The road passes an eastbound weigh station and winds east, crossing over the railroad tracks before it reaches an eastbound truck rest area. I-70/US 40 comes to a partial cloverleaf interchange withMD 27 that serves the town ofMount Airy to the north, at which point it entersCarroll County. Past this interchange, the freeway runs through wooded areas between CSX's Old Main Line Subdivision to the north and MD 144 to the south, curving southeast and crossing the South BranchPatapsco River.^[1][3]

Upon crossing the South Branch Patapsco River, I-70/US 40 entersHoward County and continues east-southeast along the Baltimore National Pike freeway through wooded areas with some fields and development, with Old Frederick Road parallel to the north and MD 144 parallel to the south. Farther east, Old Frederick Road and MD 144 continue parallel a further distance from the freeway before the freeway comes to a diamond interchange withMD 94 inLisbon. Past this interchange, the road continues through rural land with some development and comes to the exit forMD 97 inCooksville. I-70/US 40 runs east through a mix of farmland and woodland with some residential development, coming to a westbound weigh station. The freeway passes north of the Howard County Fairgrounds before it reaches a diamond interchange withMD 32 inWest Friendship. Past this interchange, the road continues east through rural land and homes before US 40 splits from I-70 for the final time at an eastbound exit and westbound entrance.^[1][3]

Upon splitting from I-70, US 40 continues southeast along Baltimore National Pike, a four-lane at-grade divided highway. The road passes through wooded areas with some residential development as it heads intoEllicott City and comes to an intersection with the eastern terminus of the section of MD 144 running between Mount Airy and Ellicott City. At this point, the road curves east and passes businesses, with Frederick Road splitting to the southeast, before it crosses theLittle Patuxent River in a wooded area and runs near suburban residential neighborhoods. The route widens to six lanes and passes through a shopping district with numerous restaurants as it comes to an interchange with theUS 29 freeway. Past this interchange, US 40 turns northeast and passes more businesses, crossing Rogers Avenue before the eastbound side becomes paralleled by aservice road that is designatedMD 984.^[1][3] The section of US 40 through Ellicott City is designated "Korean Way" and contains severalKorean American businesses.^[4][5] The road narrows to four lanes and continues northeast through wooded residential neighborhoods. The route heads into forested areas inPatapsco Valley State Park and comes to a right-in/right-out access point to the Hollofield Area of the state park before it turns southeast and passes over the Patapsco River valley on a bridge.^[1][3]

Upon crossing the Patapsco River, US 40 entersBaltimore County and continues southeast along Baltimore National Pike through more forested areas of Patapsco Valley State Park before leaving the state park. The road heads intoCatonsville, where it widens to six lanes and passes through a commercial strip of shopping centers and varieties of car dealerships and fast-food restaurants, curving to the east. The route crossesRolling Road and turns to the east-northeast, continuing past a mix of homes and businesses. US 40 comes to an interchange withI-695 (Baltimore Beltway) and heads south of theWestview Shopping Center as it continues east through commercial areas. Farther east, the road passes through a mix of residential neighborhoods and shopping centers.^[1][3]

US 40 leaves Baltimore County and enters the city ofBaltimore, where it becomes maintained by theBaltimore Department of Transportation. The road continues east past homes in West Baltimore and comes to a junction with Edmondson Avenue, where the Baltimore National Pike name ends and the road name becomes Edmondson Avenue. A short distance later, the route intersects Cooks Lane. From here, the road heads east past commercial establishments and passes north ofEdmondson-Westside High School andNew Cathedral Cemetery before it continues into urban areas ofrowhouses with some businesses. US 40 comes to an interchange with the western terminus ofUS 40 Truck at Hilton Parkway before it passes over CSX'sHanover Subdivision railroad line andGwynns Falls. Following this, the route passes north of Western Cemetery before it turns southeast onto West Franklin Street. The road curves back to the east and continues between rowhouses to the north and commercial areas to the south. US 40 splits into the one-way pair of West Mulberry Street eastbound and Franklin Street westbound, carrying three lanes in each direction, and passes under Amtrak'sNortheast Corridor railroad line at theWest Baltimore station servingMARC'sPenn Line. A short distance later, the route heads east onto a four-lane freeway stub located in a depressed alignment between West Mulberry Street and West Franklin Street, which serve asfrontage roads; this freeway stub was formerlyI-170. Along this freeway alignment, US 40 passes underUS 1, which also uses a one-way pair of North Fulton Avenue northbound and North Monroe Street southbound, and is accessed via an eastbound exit and westbound entrance with the frontage roads. The freeway widens to six lanes as it continues east, coming to an interchange withMartin Luther King Jr. Boulevard.^[2][3]

After this, the freeway ends and US 40 resumes along the one-way pair of West Mulberry Street eastbound and West Franklin Street westbound, carrying three lanes in each direction. The route intersects the northern terminus ofMD 295, which is routed along the one-way pair of North Paca Street northbound and North Greene Street southbound, and the southern terminus ofMD 129, which is routed along the one-way pair of North Paca Street northbound and Pennsylvania Avenue southbound. From here, US 40 passes south of theSeton Hill Historic District as it heads into theMount Vernon neighborhood north ofdowntown Baltimore and continues east, crossingMTA Maryland'sBaltimore Light RailLink at North Howard Street. The route crossesNorth Charles Street, at which point the name changes to East Mulberry Street eastbound and East Franklin Street westbound. US 40 intersects the southbound direction ofMD 2 atSt. Paul Street before both directions rejoin along Orleans Street, a six-lane undivided road. The route heads onto the Orleans Street Viaduct, passing over the northbound direction of MD 2 (North Calvert Street) andI-83 (with no access) in theJones Falls stream valley. After this, the road becomes a divided highway and runs through urban areas of homes and businesses in East Baltimore, heading south ofPaul Laurence Dunbar High School before passing through the campus ofThe Johns Hopkins Hospital. Past the hospital, US 40 becomes a four-lane undivided road and continues past rowhouses and some businesses. Farther east, the route intersects Pulaski Highway and heads east-northeast along four-lane undivided Pulaski Highway, passing through commercial areas with some urban homes. The road intersects the western terminus ofMD 150 at Haven Street before it passes under an abandoned railroad line and then Amtrak's Northeast Corridor. The route continues through industrial areas and passes under CSX'sBaltimore Terminal Subdivision railroad line before it widens to a six-lane divided highway and reaches a partial cloverleaf interchange withMD 151 (Erdman Avenue) and the eastern terminus of US 40 Truck that also includes a ramp to southboundI-895 accessible from eastbound US 40. A short distance later, US 40 crosses I-895, with a ramp from northbound I-895 to eastbound US 40. The road continues northeast through commercial areas and comes to a partial interchange with Moravia Road, with no eastbound entrance. Past this, US 40 reaches a partial interchange withI-95, with a ramp from westbound US 40 to southbound I-95 and a ramp from northbound I-95 to eastbound US 40; the missing movements are provided via Moravia Road and I-895.^[2][3]

US 40 from Martin Boulevard (MD 700) interchange overpass. Left photo from May 1953; right photo from August 2019

US 40 leaves Baltimore and crosses back into Baltimore County, where it becomes maintained by the state again. The route continues northeast along Pulaski Highway intoRosedale, passing businesses and coming to an intersection with the western terminus ofMD 7 (Philadelphia Road). The divided highway narrows to four lanes and passes through suburban commercial areas with some homes. US 40 comes to a cloverleaf interchange with I-695 (Baltimore Beltway), where it widens to six lanes, and heads southeast ofThe Centre at Golden Ring shopping center as it continues past businesses. The road entersMiddle River and passes near industrial parks, curving east to come to a bridge over CSX'sPhiladelphia Subdivision railroad line. The route turns back to the northeast and reaches an interchange with the northern terminus ofMD 700 (Martin Boulevard). US 40 narrows to four lanes and continues northeast through a mix of wooded areas and commercial development, with the railroad tracks parallel a short distance to the northwest. The roadway widens to six lanes as it passes through a business area. The road narrows back to four lanes and heads intoWhite Marsh, coming to an interchange withMD 43 (White Marsh Boulevard) in an area of woodland. The MD 43 interchange consists of a two-wayquadrant ramp between the two routes and a ramp from southbound US 40 to westbound MD 43. Past this interchange, the route runs through a mix of woods and businesses. Farther northeast, US 40 heads through forests near a section ofGunpowder Falls State Park and crossesGunpowder Falls. The road passes between commercial development to the northwest and wooded areas to the southeast before it comes to a bridge overLittle Gunpowder Falls.^[1][3]

Upon crossing Little Gunpowder Falls, US 40 entersHarford County and continues northeast along Pulaski Highway, with CSX's Philadelphia Subdivision parallel a short distance to the northwest. The route runs through business areas with some woods, curving east and passing through the community ofJoppa. The road comes to an intersection withMD 152 and continues intoEdgewood, heading through more commercial areas. US 40 reaches a junction with the northern terminus ofMD 755, which heads south to provide access toMD 24. Past this junction, the route heads into wooded areas and passes under MD 24 and overWinters Run before it curves northeast and intersects a two-way ramp that connects to MD 24. The road runs past businesses before it heads through wooded areas between the closely parallel CSX line to the northwest and a branch of theBush River to the southeast. US 40 passes through forests before it heads past a mix of homes and businesses inAbingdon. The road crosses the Bush River and continues between the railroad tracks to the northwest and the river to the southeast as it runs through wooded areas. The route heads northwest of an office park before it passes underMD 543 and then intersects the southern terminus of that route inRiverside, with MD 543 making a 180-degree turn to intersect US 40. Following this, US 40 runs between the CSX line to the northwest and a mix of woods and homes to the southeast before crossing Grays Run, where the name changes to South Philadelphia Boulevard. The road heads further from the railroad tracks and passes through a mix of woodland and commercial development. The route comes to an intersection with the eastern terminus of the section of MD 7 that began near Baltimore and the northern terminus ofMD 159.^[1][3]

Past this intersection, US 40 enters the city ofAberdeen and passes through commercial areas and some woods before it reaches an interchange with the northern terminus ofMD 715, which provides access to an entrance toAberdeen Proving Ground, and Hickory Drive. Following this interchange, the road becomes lined with businesses and curves to the north-northeast. The route runs a short distance to the west of Amtrak's Northeast Corridor and becomes paralleled by a service road to the west, which is designatedMD 740B east of Plater Street. In the center of Aberdeen, US 40 comes to an intersection withMD 132 west of theAberdeen station along the Northeast Corridor that serves Amtrak and MARC's Penn Line. Following this intersection, the route becomes North Philadelphia Boulevard and continues past a mix of homes and businesses. The road turns northeast and comes to an interchange withMD 22, which heads southeast to an entrance to Aberdeen Proving Ground. Past this interchange, US 40 leaves Aberdeen and runs through woodland with some development between CSX's Philadelphia Subdivision to the northwest and Amtrak's Northeast Corridor to the southeast. Upon crossing Swan Creek, the road name changes back to Pulaski Highway. The route intersects the eastern terminus of MD 132 and continues through business areas with some woods sandwiched between the two parallel railroad lines, passing the entrance toBulle Rock Golf Course. Farther northeast, US 40 enters the city ofHavre de Grace and comes to an intersection with the western terminus of a section of MD 7 that passes through the center of Havre de Grace and serves theHavre de Grace Historic District. The route heads north-northeast past businesses and some woodland, with the parallel railroad tracks heading further away. The road reaches an intersection with the eastern terminus of the MD 7 section through Havre de Grace and the eastern terminus ofMD 155 as it continues past commercial development. US 40 heads onto theThomas J. Hatem Memorial Bridge, a bridge maintained by theMaryland Transportation Authority that crosses theSusquehanna River. Upon ascending onto the bridge, the route comes to the eastboundall-electronic toll gantry and passes overMD 763 before heading northeast across the Susquehanna River.^[1][3]

While crossing the Susquehanna River, US 40 entersCecil County and passes over forestedGarrett Island before heading across more of the river. Upon reaching the east bank of the Susquehanna River, the route enters the town ofPerryville and passes over residential areas and Norfolk Southern'sPort Road Branch railroad line before descending off the Thomas J. Hatem Memorial Bridge, where it passes a pair of weigh stations. US 40 becomes state-maintained again and follows four-lane divided Pulaski Highway northeast to an intersection withMD 222. Following this, the road passes through business areas with some woodland to the south. The route becomes paralleled by CSX's Philadelphia Subdivision to the north for a short distance before it passes east-northeast between commercial development to the north and residential areas to the south. US 40 leaves Perryville and continues through a mix of farm fields and woods with some commercial development, coming to an intersection with the eastern terminus of a section of MD 7 that serves Perryville. The route passes a pair of abandoned weigh stations as it runs through a mix of woods and sand quarries, with another section of MD 7 splitting to the southeast. The road continues northeast and passes north of a sand quarry as it continues through forested areas with some residential and commercial development including warehouses.^[1][3]

US 40 approaches the town ofNorth East and heads into business areas, reaching an intersection withMD 272. It briefly passes through a sliver of North East as it passes more development before it curves east, crossingNorth East Creek and Little North East Creek in a wooded area. The road passes near a cluster of businesses near the Mechanics Valley Road junction and continues east through forested areas with some residential and commercial development. Farther east, US 40 reaches an intersection with the eastern terminus of the section of MD 7 passing through North East and the southern terminus ofMD 279. Past this intersection, the route heads into the town ofElkton and curves east-southeast, passing over Little Elk Creek and Amtrak's Northeast Corridor in a wooded area. The road runs through commercial areas with some homes before it comes to a bridge overBig Elk Creek in woodland. US 40 heads into business areas, crossingMD 213 and curving east at the White Hall Road intersection. The route turns to the north-northeast and passes commercial development with some woodland, coming to a junction with the eastern terminus of a section of MD 7 that leads into the center of Elkton. US 40 heads through business areas and intersects the southern terminus ofMD 781 before it reaches theDelaware state line, where US 40 continues into that state along Pulaski Highway.^[1][3]

TheNational Road was opened fromCumberland on thePotomac River and the terminus of the parallelChesapeake and Ohio Canal coming fromGeorgetown in the newly established national capital ofWashington, D.C., going west and northwest intoPennsylvania, and beyond toWheeling, Virginia on theOhio River, southwest ofPittsburgh at the point of theForks of the Ohio, in the 1810s. Theturnpikes constructed and now operated by private stockholder companies connecting Cumberland east toBaltimore operated as theCumberland Turnpike (Cumberland toConococheague, chartered 1812, and not to be confused with an alternate name for the National Road),^[6] theHagers-Town and Conococheague Turnpike (Conococheague toHagerstown, chartered 1817),^[7] theHager's-Town and Boonsborough Turnpike (Hagerstown toBoonsboro, chartered 1819), and theBaltimore and Frederick-town Turnpike (Boonsboro through Frederick to Baltimore, chartered 1805), completed in 1824. These feeders of the National Road were collectively called the Bank Road, since they were financed largely by Maryland banks.^[8] To the east of Baltimore, theBaltimore and Havre-de-Grace Turnpike, chartered in 1813 and opened 1825,^[9] went northeast from Baltimore toHavre de Grace on the west bank of theSusquehanna River, and public roads continued fromPerryville, across the Susquehanna River on its east bank from Havre de Grace toElkton near the "Head of Elk" on theElk River at the northern end of theChesapeake Bay, and thence intoDelaware. Of all the aforementioned roads, few still carry US 40 today.

West of Baltimore, the National Road and the Bank Road were incorporated into the National Old Trails Road in the mid-1910s.^[10] East of Havre-de-Grace, the road became part of the Capitol Trail linking Philadelphia and Atlanta via Washington,^[11] though it took a more northerly route than the modern route to service Bel Air viaMD 22 and US 1. In 1926, the designation of US 40 superseded both of these routes.

As traffic increased through the early 20th century, new roadway bypassed the original highways, with the old alignments receiving new monikers. With the construction of the Pulaski Highway east of Baltimore, the old alignment becameMD 7.^[12] By 1939, a bypass of Ellicott City had been constructed, signed as US 40 Bypass.^[13] In 1948, the two alignments were swapped, with the old highway becoming US 40 Alternate,^[14] and with the construction of a new freeway to Lisbon, both old alignments became part of MD 144.^[15] By 1948, a new alignment had also been built from Frederick to Hagerstown, and the old alignment became the currentUS 40 Alternate. With the construction of I-70 and I-68, the existing segments of US 40 at freeway standards (the road from Frederick to Baltimore, the road west of Hancock, and the bypass ofUS 40 Scenic constructed in 1965) were incorporated into the new interstates. The sections of at-grade highway bypassed by I-68 had US 40 rerouted off of them onto the new interstate, with the section from Cumberland to Keyser's Gate becoming a newUS 40 Alternate, with remaining sections becoming an extension of MD 144.

From 1960 to 1969, plans for anEast-West Expressway, which was to be a continuation ofI-70N into the city before ending as a segment ofI-95, called for part of it to be built in the Franklin-Mulberry corridor, which was then the one-way couplet for US 40. In 1969, the East-West Expressway was scrapped and replaced with a new, differently-routed spur numbered asI-170, which did get built in the same corridor, but was cancelled by 1989. As a result, US 40 was rerouted onto the 1.39-mile (2.24 km) freeway, with Mulberry and Franklin streets acting as local frontage roads.

The long arches of the US 40 bridge over the upper / western branches of thePatapsco River inEllicott City, originally constructed in 1936, were replaced in a project that started in the spring of 2011 and was expected to be completed in 2013. During the bridge replacement, temporary parallel bridges were constructed to serve traffic for the first time in a major bridge project in Maryland.^[16]

As part of the east–westRed Line light rail project that was cancelled in 2015 by newGovernor of MarylandLarry Hogan and then revived in 2023 by his successorWes Moore, segments of Edmondson Avenue and Franklin Street on the west side of the city are to be widened to allow construction of the future east–west light rail line inside the median area. The Red Line will also utilize the median of the short US 40 expressway stub (formerly planned for the cancelled extension of I-70) along the Franklin Street - Mulberry Street corridor in West Baltimore.

In December 2016, Governor Hogan designated the portion of US 40 through Ellicott City as "Korean Way", paying homage to the many Korean American businesses and residents of Howard County.^[4][5]

Prior to the 1960s,racial segregation was legal by law in Maryland, where all public establishments enforced segregation under theJim Crow laws. African Americans traveling along US 40 in Maryland were routinely denied service at establishments such as hotels, shops, and restaurants; in his bookReady for Revolution, Black civil rights activistStokely Carmichael wrote that he "developed a deep hatred—one shared by many—for Route 40" after being regularly denied service at restaurants along the route.^[17]

In June 1961, theChadian ambassador to the U.S., Adam Malick Sow, was denied service by a white-owned diner by US 40 nearEdgewood, which sparked aninternational incident and made headline news in Africa and Asia. After Sow informed PresidentJohn F. Kennedy of the incident, thefederal government, which viewed such incidents as a foreign policy embarrassment amidst theCold War, began pressuring Maryland business owners to start serving African diplomats. In response to news of segregation along US 40, theCongress of Racial Equality startedpicketing along the route, and in 1963 Maryland passed legislation outlawing racial discrimination in public establishments, which was described by professor James Karmel as the "first state civil rights act".^[18]

County	Location	mi [1][2]	km	Exit	Destinations	Notes
Garrett	​	0.00	0.00		US 40 west /Historic National Road –Uniontown	Pennsylvania state line; western terminus of US 40 in Maryland
	Keyser's Ridge	3.41	5.49		US 40 Alt. east /Historic National Road –Grantsville,Cumberland
		3.74	6.02	14	I-68 west (National Freeway) /US 219 south (Garrett Highway) –Morgantown,Oakland	Split into exits 14A (US 219) and 14B (US 40); west end of concurrencies with I-68 and US 219
	Grantsville	9.12	14.68	19	MD 495 (Bittinger Road) –Grantsville,Swanton
	​	12.18	19.60	22	US 219 north /US 219 Bus. north (Chestnut Ridge Road) –Meyersdale, PA	East end of concurrency with US 219; southern terminus of US 219 Bus.
	​	13.90	22.37	24	Lower New Germany Road (MD 948D)
	Finzel	19.70	31.70	29	MD 546 (Finzel Road) –Finzel
Allegany	Frostburg	23.24	37.40	34	Midlothian Road (MD 736) –Frostburg
		24.93	40.12	36	MD 36 (New Georges Creek Road) –Frostburg,Westernport
	La Vale	29.12	46.86	39	US 40 Alt. (National Highway) –La Vale	No exit eastbound; eastbound entrance ramp is fromMD 53
		29.85	48.04	40	US 220 Truck south (Vocke Road)	No entrance westbound; Vocke Road is unsignedMD 658
	Cumberland	31.46	50.63	41	Seton Drive toMD 49	Westbound exit only
		32.24	51.89	42	US 220 south (McMullen Highway) / Greene Street north –McCoole,Keyser, WV	West end of concurrency with US 220
		33.51	53.93	43A	Johnson Street –Ridgeley, WV	Eastbound exit and entrance
		33.51	53.93	43A	Beall Street –Ridgeley, WV	No eastbound exit
		33.80	54.40	43B	MD 51 south (Industrial Boulevard) –Airport
		33.82	54.43	43C	Downtown
		34.14	54.94	43D	Maryland Avenue	Right-in/right-out interchanges
		34.77	55.96	44	US 40 Alt. west (Baltimore Avenue) /MD 639 south (Willowbrook Road) /Historic National Road
		35.69	57.44	45	Hillcrest Drive	Right-in/right-out interchanges with Rannells Road eastbound and Hillcrest Drive westbound, which are unsignedMD 952 andMD 952A, respectively
		36.39	58.56	46	MD 144 (Naves Cross Road)	Westbound exit and entrance
		37.09	59.69	47	US 220 north /MD 144 /Historic National Road –Bedford	Signed as exit 46 eastbound; east end of concurrency with US 220
	​	41.18	66.27	50	Pleasant Valley Road (MD 948AD) –Rocky Gap State Park
	​	42.42	68.27	52	MD 144 east (National Pike)	Eastbound exit, westbound entrance
	Flintstone	45.87	73.82	56	MD 144 (National Pike) –Flintstone	Westbound ramps are withMD 948AM
	​	52.84	85.04	62	US 40 Scenic (Fifteen Mile Creek Road)
	​	54.11	87.08	64	M.V. Smith Road (MD 948AL)
	​	58.64	94.37	68	Orleans Road (MD 948Z)
	​	61.56	99.07	72	US 40 Scenic (National Pike) / High Germany Road / Swain Road	West end of concurrency with US 40 Scenic; High Germany Road is unsignedMD 948Y
Washington	​	63.51	102.21	74	US 40 Scenic east (National Pike) / Mountain Road	Eastbound exit, westbound entrance; Mountain Road is unsignedMD 903; east end of concurrency with US 40 Scenic
	​	67.07	107.94	77	US 40 Scenic west (National Pike) /MD 144 east (Western Pike) / Woodmont Road
	Hancock	71.01	114.28	82 1	I-70 west (Eisenhower Memorial Highway) /US 522 –Breezewood,Hancock,Winchester	Split into exits 82A (US 522), 82B (I-70 / US 40), and 82C (I-70 / US 522) eastbound; split into exits 1A (I-68 / US 40) and 1B (US 522 south) westbound; eastern terminus of I-68; west end of concurrency with I-70
		73.50	118.29	3	MD 144 (Main Street) /Historic National Road /C&O Canal Byway –Hancock	No westbound entrance
	​	74.40	119.74	5	MD 615 (Millstone Road)	Eastbound exit, westbound entrance
	​	75.85	122.07	5	MD 615 (Millstone Road)	Westbound exit, eastbound entrance
	Indian Springs	79.17	127.41	9	I-70 east (Eisenhower Memorial Highway) /C&O Canal Byway –Hagerstown	Eastbound exit from and westbound entrance to I-70; east end of concurrency with I-70
	Clear Spring	86.57	139.32		MD 68 east (Mill Street) toI-70 –Williamsport
	​	88.97	143.18		MD 57 north (St. Paul Road)
	Huyett	93.51	150.49		MD 63 (Greencastle Pike) toI-70 –Cearfoss,Williamsport
	Hagerstown	94.75	152.49		MD 144 east (Washington Street)
		96.23	154.87		I-81 (Maryland Veterans Memorial Highway) toI-70 –Roanoke,Harrisburg	I-81 Exit 6
		96.61	155.48		MD 910 south (Western Maryland Parkway)	Officially MD 910C
		97.63	157.12		US 11 (Burhans Boulevard)
					Historic National Road (Potomac Street)	ToUS 40 Alt
		98.68	158.81		MD 64 east (Cleveland Avenue) –Smithsburg
		101.72	163.70		I-70 (Eisenhower Memorial Highway) toI-81 –Hancock,Frederick	I-70 Exit 32
	Beaver Creek	104.53	168.22		MD 66 (Mapleville Road) toI-70 –Smithsburg,Boonsboro
Frederick	Myersville	111.03	178.69		MD 17 (Wolfsville Road) –Middletown
	Braddock Heights	118.41	190.56		I-70 west (Eisenhower Memorial Highway) –Hagerstown	I-70 Exit 48; westbound exit, eastbound entrance
	Frederick	119.68	192.61		US 40 Alt. west /Historic National Road –Braddock Heights,Middletown	No direct access from eastbound US 40 to westbound US 40 Alternate or from eastbound US 40 Alternate to westbound US 40
		121.09	194.88	13	US 15 north (Frederick Freeway) /Historic National Road (Patrick Street east) –Gettysburg	split into exits 13A (Patrick Street) and 13B (US 40 west); west end of concurrency with US 15
		121.82	196.05	12	US 15 south /US 340 west (Jefferson National Pike) / Jefferson Street east –Leesburg,Charles Town	East end of concurrency with US 15
		122.44	197.05	53	I-70 west /I-270 south (Eisenhower Memorial Highway) –Hagerstown,Washington	Split into exits 53A (I-270) and 53B (US 40 west); west end of concurrency with I-70
		123.60	198.91	54	MD 85 (Buckeystown Pike) toMD 355 / Market Street	Single-point urban interchange
		124.15	199.80	55	South Street	Westbound ramps are with Monocacy Boulevard
		124.68	200.65	56	MD 144 (Patrick Street)	No westbound entrance
	Bartonsville	128.04	206.06	59	MD 144 west (National Road)	No eastbound exit
	New Market	131.75	212.03	62	MD 75 (Green Valley Road) –Libertytown,Hyattstown
Carroll	Mount Airy	137.19	220.79	68	MD 27 (Ridge Road) –Mount Airy,Damascus
Howard	Lisbon	142.58	229.46	73	MD 94 (Woodbine Road) –Lisbon,Woodbine
	Cooksville	145.75	234.56	76	MD 97 (Hoods Mill Road) –Westminster,Olney
	West Friendship	149.42	240.47	80	MD 32 (Sykesville Road) –Sykesville,Clarksville
		151.54	243.88	82	I-70 east –Baltimore	Eastbound exit from and westbound entrance to I-70; east end of concurrency with I-70
	Ellicott City	154.13	248.05		MD 144 west (Frederick Road) /Historic National Road
					Historic National Road (Frederick Road)
		157.10	252.83		US 29 (Columbia Pike) toI-70 –Columbia,Frederick	US 29 Exit 24
		159.25	256.29		Patapsco Valley State Park Hollofield Area	Right-in/right-out interchanges in both directions
Baltimore	Catonsville	162.28	261.16		I-695 (Baltimore Beltway) –Glen Burnie,Towson	I-695 Exit 15
Baltimore City		165.93	267.04		US 40 Truck east (Hilton Parkway) / Hilton Parkway south	Cloverleaf interchange
		167.31	269.26		Mulberry Street east toUS 1 (Monroe Street/Fulton Avenue)	Eastbound exit, westbound entrance (from Franklin Street)
		168.36	270.95		Martin Luther King Jr. Boulevard	Diamond interchange
		168.57	271.29		MD 295 south (Greene Street)	Greene Street is one-way southbound
		168.64	271.40		MD 129 north (Paca Street)	Paca Street is one-way northbound
		169.02	272.01		Charles Street north	Charles Street is one-way northbound
		169.09	272.12		MD 2 south (St. Paul Street)	No access to northbound MD 2
		171.86	276.58		MD 150 east (Haven Street)
		172.59	277.76		MD 151 (Erdman Avenue) /US 40 Truck west /I-895 south (Harbor Tunnel Thruway)	Cloverleaf interchange; movements from eastbound US 40 to northbound MD 151 and from northbound MD 151 to eastbound US 40 made via Armistead Way; I-895 Exit 13
		173.58	279.35		Moravia Road toI-895 /I-95 north	No eastbound entrance
		173.76	279.64		I-95 south –Washington	I-95 Exit 61; ramps from westbound US 40 to southbound I-95 and northbound I-95 to eastbound US 40
Baltimore	Rosedale	174.12	280.22		MD 7 east (Philadelphia Road)
		176.63	284.26		I-695 (Baltimore Beltway) / Golden Ring Road north –Essex,Towson	I-695 Exit 35
	Middle River	177.96	286.40		MD 700 south (Martin Boulevard)	Trumpet interchange
	White Marsh	180.84	291.03		MD 43 (White Marsh Boulevard) toI-95	Two-way ramp between US 40 and MD 43 plus a ramp from westbound US 40 to westbound MD 43
Harford	Joppatowne	187.54	301.82		MD 152 (Magnolia Road/Mountain Road) toI-95
	Edgewood	189.21	304.50		MD 755 south (Edgewood Road) to Edgewood Road north south /MD 24
		189.78	305.42		ToMD 24 (Vietnam Veterans Memorial Highway) –Edgewood,Bel Air	Two-way ramp between US 40 and MD 24 is MD 24D (Otter Creek Ramp)
	Riverside	193.93	312.10		MD 543 north (Riverside Parkway) toI-95
	Aberdeen	196.13	315.64		MD 7 west /MD 159 south (Old Philadelphia Road)
		196.94	316.94		MD 715 south (Short Lane) / Hickory Drive –Aberdeen Proving Ground	Trumpet interchange
		198.52	319.49		MD 132 (Bel Air Avenue)	Officially MD 132B
		199.03	320.31		MD 22 (Aberdeen Thruway) toI-95 –Aberdeen Proving Ground,Bel Air	Partial cloverleaf interchange
	Havre de Grace	200.28	322.32		MD 132 west (Oakington Road)
		201.72	324.64		MD 7 east (Revolution Street) –Havre de Grace	Officially MD 7A
		203.10	326.86		MD 7 west (Otsego Street) /MD 155 west (Ohio Street) toI-95 / Otsego Street west –Havre de Grace,Churchville	Officially MD 7A; last eastbound exit before toll
Susquehanna River		203.41– 204.90	327.36– 329.75	Thomas J. Hatem Memorial Bridge (eastbound toll;E-ZPass orpay-by-plate)
Cecil	Perryville	205.21	330.25		MD 222 (Perryville Road/Aiken Avenue) toI-95 –Port Deposit,Perryville
	​	207.98	334.71		MD 7 west (Principio Furnace Road) –Perryville	Officially MD 7B
	​	208.45	335.47		MD 7 east (Old Philadelphia Road) –Charlestown,North East	Officially MD 7C
	North East	212.33	341.71		MD 272 (Mauldin Avenue/North East Road) toI-95 –Cecil College,Bay View,North East,Charlestown
	Elkton	217.43	349.92		MD 7 west (Old Philadelphia Road) /MD 279 north (Elkton Road) toI-95 –North East,Newark	Officially MD 7C
		218.91	352.30		MD 213 (Bridge Street/Augustine Herman Highway) –Elkton,Chesapeake City
		220.25	354.46		MD 7 west (Delaware Avenue) –Elkton	Officially MD 7D
		221.08	355.79		MD 781 north (Delancy Road)
		221.31	356.16		US 40 east (Pulaski Highway) –Glasgow	Delaware state line; eastern terminus of US 40 in Maryland
1.000 mi = 1.609 km; 1.000 km = 0.621 mi       Concurrency terminus       Electronic toll collection       Incomplete access

• Maryland Roads portal

Wikimedia Commons has media related toU.S. Route 40 in Maryland.

• US 40 at MDRoads.com
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• Maryland Roads - US 40
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U.S. Route 40
Previous state: Pennsylvania	Maryland	Next state: Delaware

• U.S. Highways in Maryland
• U.S. Route 40
• Roads in Garrett County, Maryland
• Roads in Allegany County, Maryland
• Roads in Washington County, Maryland
• Roads in Frederick County, Maryland
• Roads in Carroll County, Maryland
• Roads in Howard County, Maryland
• Roads in Baltimore
• Roads in Baltimore County, Maryland
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• Roads in Cecil County, Maryland
• Limited-access roads in Maryland

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