I-78 highlighted in red | ||||
| Route information | ||||
| Maintained byNJDOT,DRJTBC,NJTA, andPANYNJ | ||||
| Length | 67.83 mi[1][2] (109.16 km) | |||
| Existed | 1958–present | |||
| History | Completed in 1989 | |||
| NHS | Entire route | |||
| Restrictions | Nohazardous goods inHolland Tunnel | |||
| Major junctions | ||||
| West end | ||||
| Major intersections |
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| East end | ||||
| Location | ||||
| Country | United States | |||
| State | New Jersey | |||
| Counties | Warren,Hunterdon,Somerset,Union,Essex,Hudson | |||
| Highway system | ||||
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Interstate 78 (I-78) is an east–west route stretching fromUnion Township, Lebanon County, Pennsylvania, toNew York City. InNew Jersey, I-78 is called thePhillipsburg–Newark Expressway and theNewark Bay Extension of theNew Jersey Turnpike. The highway runs for 67.83 miles (109.16 km) in the northern part of the state of New Jersey from theInterstate 78 Toll Bridge over theDelaware River at thePennsylvania state line inPhillipsburg, Warren County, east to theHolland Tunnel under theHudson River at theNew York state line inJersey City, Hudson County. The Phillipsburg–Newark Expressway portion of I-78, formally called theLightning Division Memorial Highway, runs from the Phillipsburg area east across rural areas of Western New Jersey before entering suburban areas inSomerset County. The road crosses theWatchung Mountains, widening into alocal–express lane configuration atRoute 24 as it continues through urban areas toNewark. Here, I-78 intersects the mainline of the New Jersey Turnpike (I-95) and becomes the Newark Bay Extension, crossing theNewark Bay Bridge and continuing to Jersey City. The route, along withRoute 139, follows aone-way pair of surface streets to the Holland Tunnel.
In 1927,Route 11 was legislated as a high-speed bypass ofU.S. Route 22 (US 22) betweenWhitehouse andWarren Township but was never built. The earliest parts of I-78 to be built were the Holland Tunnel in 1927 and the Newark Bay Extension. With the creation of theInterstate Highway System in the 1950s, a highway was planned along US 22 through northern New Jersey, becoming I-78 in 1958. The highway between Phillipsburg and Newark was built in various stages from the 1960s to 1989, with the final segment opening at the I-78 Toll Bridge. The section of highway through the Watchung Mountains and across Newark garnered opposition from environmentalists and residents who were worried about the effects of the highway. In addition, there was opposition to building I-78 through Phillipsburg, which resulted in the alignment to the south of theLehigh Valley. In the 2000s, I-78 was completely rebuilt between Route 24 and theGarden State Parkway. In addition, missing movements between the parkway and I-78 were completed in 2010.[3]

I-78 enters New Jersey fromPennsylvania on theI-78 Toll Bridge over theDelaware River and theBelvidere and Delaware River Railway, heading intoPhillipsburg, Warren County.[2] The highway heads south into agricultural areas as a six-lane freeway that is maintained by theDelaware River Joint Toll Bridge Commission (DRJTBC), enteringPohatcong Township a short distance after the river.[2][4] The freeway makes a turn to the east as it briefly passes through a corner ofAlpha before coming back into Pohatcong Township. Bypassing the center of Alpha to the south, I-78 passes under Norfolk Southern Railway'sLehigh Line and has two more segments that enter the Alpha borough limits before coming to an interchange withUS 22 and the western terminus ofRoute 173. At this point, US 22runs concurrently with I-78, and the road comes intoGreenwich Township. At this point, theNew Jersey Department of Transportation (NJDOT) takes over maintenance of the road. I-78/US 22 continues east through Greenwich Township, coming to a westbound exit and eastbound entrance with South Main Street (CR 637). The road turns southeast and has an eastbound exit and westbound entrance with Bloomsbury Road (CR 632) inFranklin Township.[2] Within the ramps for this interchange, there areweigh stations in both directions.[4]
A short distance after this interchange, I-78/US 22 crosses theMusconetcong River intoBloomsbury, Hunterdon County. In Bloomsbury, the road has an interchange with Route 173.[2] After this interchange, the freeway entersBethlehem Township, with Route 173 closely running to the north of I-78/US 22.[2][4] The road comes to a bridge over Norfolk Southern Railway's Central Running Track line and hasrest areas in both directions before it passes over Norfolk Southern Railway's Lehigh Line and turns southeast to cross theMusconetcong Mountain.[4] As the freeway crosses the Jugtown Mountain, there is an automaticdeicing spray, the first such to be installed in New Jersey.[5]
The freeway turns east again and entersUnion Township, coming to an interchange with Pattenburg Road (CR 614) and Route 173.[2] From here, I-78/US 22 continues east directly to the south of Route 173, coming to another interchange with that route as well as Mechlin Corner Road (CR 625). Entering more commercial areas, Route 173 merges onto I-78/US 22 at exit 13.[2][4] At exit 15, the highway intersects Pittstown Road (CR 513), and Route 173 splits from I-78/US 22 by heading north on CR 513. At this point, the freeway entersFranklin Township briefly at exit 15 and then entersClinton where it crosses theSouth Branch of the Raritan River.[2] I-78/US 22 turns northeast and leaves Clinton forClinton Township, where it has an eastbound exit and westbound entrance for Route 173 that also provides access toRoute 31.[2][4] Immediately after is the interchange with Route 31.[2] At the next interchange near the community ofAnnandale, US 22 splits from I-78 onto a four-lane surface highway, heading closely to the south of that route.[2][4]
Immediately after the split, I-78 passes over NJ Transit'sRaritan Valley Line and runs through rural areas with increasing suburban development. The freeway runs throughLebanon, where an exit for Cokesbury Road (CR 639) provides access to the town and theRound Valley Recreation Area. After running through Clinton Township and intoReadington Township, US 22 turns southeast while I-78 continues a due east course. InTewksbury Township, there is an interchange with Oldwick Road (CR 523) that also provides access toCR 517.[2][4] After this exit, the highway crosses back into Readington.[2]


After crossing theLamington River, I-78 comes intoBedminster, Somerset County, continuing east through more woods and farms with some suburban residential areas.[2][4] Upon entering Somerset County, there is an exit for Rattlesnake Bridge Road (CR 665) (signed asCR 523 Spur). The next interchange, exit 29, is called the Vincent R. Kramer Interchange.[2] It is atI-287, which serves as a bypass aroundNew York City.[2][4] At this point, I-78 carries four eastbound lanes and three westbound lanes as the median widens.[2] The road enters wooded suburban areas and crosses theSecond Watchung Mountain, running through a corner ofBridgewater Township, where there is a westboundscenic overlook, before coming intoBernards Township.[2][4] The eastbound direction narrows back to three lanes before the interchange with Martinsville Road (CR 525), at which point the freeway crosses intoWarren Township. The road heads east along the southern bank of theDead River, coming to exit 36 for King George Road (CR 651). I-78 heads farther south of the Dead River as it comes to the interchange with Hillcrest Road (CR 531). Past Hillcrest Road (CR 531), the highway turns to the northeast and comes to an interchange with Drift Road/Dale Road that provides access to US 22.[2] At this point, I-78 runs across the Second Watchung Mountain again intoWatchung.[4]
The freeway crosses theGreen Brook intoBerkeley Heights, Union County, reaching exits for Diamond Hill Road (CR 655) and McMane Avenue (CR 640). The latter is an eastbound exit and entrance that also provides access to parallel Glenside Avenue (CR 527).[2] At this point, I-78 runs between Second Watchung Mountain to the northwest and theWatchung Reservation to the southeast.[4] Along the reservation border, the road passes under Nikesite Road before coming intoSummit, where there is an overpass that serves as awildlife crossing. There is an eastbound exit and westbound entrance with Glenside Avenue (CR 527) as it heads away from the Watchung Reservation and into more suburban surroundings. It briefly forms the border between Summit to the northwest andMountainside to the southeast before coming intoSpringfield Township. The freeway passes near theFirst Watchung Mountain before coming to the interchange withRoute 24, where suburban development becomes more dense.[2][4]
At Route 24, I-78 divides intolocal–express lanes, with three express and three local lanes eastbound and two express and three local lanes westbound. In this section of the highway, most access is via the local lanes, though the next exit forRoute 124 includes a direct westbound onramp to the express lanes. Before Route 124, I-78 briefly runs east throughMillburn, Essex County, and Springfield again before enteringUnion Township at the interchange. Past Route 124, I-78 carries a 3-2-2-3–lane configuration and comes to partial interchanges with Vauxhall Road (CR 630) and Burnet Avenue (CR 633). The next interchange along the highway provides access to theGarden State Parkway along the border of Union andHillside.[2] The road turns northeast again into Hillside, heading into more urbanized settings.[4] In Hillside, I-78 passes underConrail Shared Assets Operations' (CSAO) Irvington Industrial Track line and has an eastbound exit and westbound entrance to Winans Avenue.[2]


I-78 briefly passes through a corner ofIrvington in Essex County before continuing intoNewark. Upon entering Newark, the road has an interchange serving Lyons Avenue (CR 602) and Wainwright Street.[2] Following this, the freeway passes near urban neighborhoods before coming to exit 56.[2][4] This largesemi-directional T interchange was originally meant to serve the unbuiltRoute 75, which would have connected toI-280. The large flyover ramps constructed were converted to exit ramps to Irvine Turner Boulevard with full access to the local and express lanes.[6] Past this, the roadway passes over CSAO'sLehigh Line (which also carries NJ Transit's Raritan Valley Line), Frelinghuysen Avenue (Route 27), and Amtrak'sNortheast Corridor. The final interchange on the free part of I-78 is the massive complex to the north ofNewark Airport, called theNewark Airport Interchange, with ramps to and fromUS 1-9, US 22,Route 21, and many local roads. Several ramps provide access to the express lanes.[2][4] Just to the east, the local and express lanes rejoin at the toll gate for theNew Jersey Turnpike, at which point I-78 becomes maintained by theNew Jersey Turnpike Authority (NJTA), following the Newark Bay Extension of the New Jersey Turnpike. An interchange just beyond the toll booth provides full access toI-95, the mainline of the New Jersey Turnpike.[2] I-78 here becomes a four-lane highway, heading over the New Jersey Turnpike and CSAO'sChemical Coast Secondary and Corbin Street Lead lines before passing by thePort Newark–Elizabeth Marine Terminal.[2][4]
I-78 crosses theNewark Bay on theNewark Bay Bridge intoBayonne, Hudson County. As it entersJersey City, exit 14A, numbered as part of the New Jersey Turnpike, provides access toRoute 440.[2] Within this interchange, the road passes over CSAO's Bayonne Industrial Track and Greenville Industrial Track lines. From here, the freeway turns northeast on an elevated alignment and passes industrial areas of Jersey City, with CSAO'sNational Docks Branch line parallel to the northwest.[4] The next interchange, exit 14B, is for Bayview Avenue and provides access toLiberty State Park.[2][4] After this interchange, I-78 comes to exit 14C, the number given to the toll plaza at the end of the turnpike extension.[2] After the toll plaza, there is an exit for apark and ride lot at theLiberty State Park Station along NJ Transit'sHudson–Bergen Light Rail line.[2][4] Continuing north, the road passes over the Hudson–Bergen Light Rail line before there is an exit for Columbus Drive and Montgomery Street.[2] Past this interchange, the highway crosses PATH'sNewark–World Trade Center line. I-78 heads down to surface level and passes over CSAO's National Docks Branch line twice before it merges withRoute 139.[2][4]
From here, I-78 and Route 139 pass through business areas as aone-way pair that follows six-lane 12th Street eastbound and six-lane 14th Street westbound. This segment of the route is under the jurisdiction of thePort Authority of New York and New Jersey (PANYNJ) and is also known asBoyle Plaza. It runs on surface streets with traffic lights, an example of asurface section of the Interstate Highway.[2][4] The first intersection is withJersey Avenue (CR 631), which heads toDowntown Jersey City andHoboken.[4] It intersects with the one-way northbound Erie Street (CR 633) next before crossing one-way southbound Grove Street (CR 635).[2] After Grove Street (CR 635), the road crosses the intersection of Marin Boulevard (CR 637) nearNewport Centre just to the south. Past this intersection, the eastbound direction comes to the toll gantry for theHolland Tunnel.[4] From here, the concurrency enters the Holland Tunnel under theHudson River, which carries two lanes in each direction. Route 139 ends at the New Jersey–New York state line within the tunnel and I-78 continues into theNew York City borough ofManhattan.[2][4]



The oldest section of I-78, theHolland Tunnel, was built in September 1927. The tunnel pre-dated the Interstate Highway System, as a commuter route linkingJersey City, New Jersey, andLower Manhattan. Six months after it was opened, 3.66 million passengers had used the tunnel.[7] In 1927, Route 11 had legislatively approved as a high-speed bypass of US 22, running fromRoute 28 inWhitehouse east toRoute 29 inWarren Township, roughly following the alignment of present-day I-78; it was never built.[8][9]
The Newark Bay Extension of the New Jersey Turnpike was the firstlimited-access section of I-78 to be built in the state of New Jersey. The 8.2-mile-long (13.2 km) expressway was opened in 1956 to provide access from the New Jersey Turnpike mainline to the Holland Tunnel.[10][11] At this time, the Interstate Highway System was established and a route was planned to run east–west from theHarrisburg, Pennsylvania, area to New York City, running across the northern part of New Jersey from Phillipsburg to Jersey City along the US 22 corridor.[12] This freeway was originally planned as FAI Corridor 102 and I-80 before it became I-78 in 1958.[13][14]
The part of I-78 between exit 3 and exit 13 opened in the 1960s; this segment runs concurrently with US 22, and the old alignment of US 22 became Route 173. In building the road between Pattenburg Road (CR 614) and exit 13, the eastbound lanes of US 22 became westbound I-78 and the westbound lanes of US 22 became the Route 173 frontage road. By 1969, I-78 had also been completed between exit 13 and Martinsville Road (CR 525).[15] In July 1963, GovernorRichard J. Hughes approved a plan to build I-78 through the city of Newark at a cost of $205 million (equivalent to $1.6 billion in 2024[16]). This plan had been opposed by several communities along the route.[17] The section of I-78 between Route 24 and the New Jersey Turnpike was completed in the mid-1970s.[18] Along this stretch, exit 56 was to connect to the proposedRoute 75 freeway, which was never built.[19]
The section of freeway between Martinsville Road (CR 525) and Drift Road/Dale Road (exit 41) inWatchung was completed in 1974. The section from Drift Road/Dale Road to Route 24 (exit 48) in Springfield was delayed because ofenvironmental impacts to the Watchung Reservation. In order to mitigate opposition to the original plan, that was shifted closer to the northern edge of the reservation, which required extensive cuts into the Second Watchung Mountain. Extra land was added to the Nikesite Road overpass and a separate elevatedwildlife crossing was built to allow for animal migration. The road was also designed to use a narrowerright-of-way with no median strip and just ajersey barrier dividing the highway, to minimize the amount of rock to be removed. This stretch of I-78 opened in 1986.[20]
A section of I-78 in Newark was closed off in August 1989 when a debris pile under a bridge caught fire and damaged the elevated highway. The road was opened nine days after the fire occurred.[21] The westernmost section of I-78 in New Jersey opened in November 1989 after a more northerly alignment along present day US 22 through Phillipsburg was rejected due to community opposition.[22] This led to I-78 being rerouted to the south of theLehigh Valley in Pennsylvania and New Jersey.[23] The additional length of roadway that resulted from this rerouting is the reason exit numbers 3 through 52 (which were assigned before this westernmost section opened) are mismatched by approximately one mile (1.6 km) when compared to their corresponding milemarker.
I-78, like many other highways in New Jersey, once had solar powered emergencycallboxes every one mile (1.6 km), however, with the advent of cellphones, the usage of these callboxes became extremely limited. To save on maintenance costs, NJDOT removed these call boxes in 2005.[24]
From 2006 to 2007, the highway between Route 24 (exit 48) and theGarden State Parkway (exit 52) was rebuilt. This included redecking of bridge decks and covering the deteriorated concrete pavement with an asphalt overlay.[25] Exit 52 was reconstructed due to missing ramps from the Garden State Parkway and I-78 since theI-287 connection was canceled. Construction began in June 2008, with the ramp from the northbound Garden State Parkway to westbound I-78 being completed in September 2009.[18] The connection between the southbound Garden State Parkway and eastbound I-78 was completed in December 2010.[3] In 2012–2013, the deteriorating concrete surface of I-78 between the Garden State Parkway (exit 52) and US 1/9 and US 22 (exit 57) was resurfaced with an asphalt overlay; this had been the last section of I-78 within New Jersey that was still concrete.[citation needed]
In the early 2020s, the NJTA announced plans to widen its section of I-78, between I-95 and Jersey City, from four to six lanes. Preliminary studies for the project began in 2021; at the time, the project was slated to begin in 2023 and be complete in 2026.[26] The project faced significant opposition from residents of neighboring communities.[27][28] The project, originally budgeted at $4.7 billion, had increased to $10.6 billion by late 2022.[26][29]
The section of 12th Street east of Marin Boulevard, which carries the eastbound I-78 andRoute 139 toward the Holland Tunnel in Jersey City, was narrowed from six to four lanes afteropen road tolling wasimplemented at the Holland Tunnel.[30] Subsequently, in 2025, theUnited States Department of Transportation awarded a $25 million grant to thePANYNJ to narrow the stretch of 12th Street between Jersey Avenue and Marin Boulevard.[30][31]
| County | Location | mi[2] | km | Exit | Destinations | Notes |
|---|---|---|---|---|---|---|
| Delaware River | 0.00 | 0.00 | – | Continuation intoPennsylvania | ||
| I-78 Toll Bridge (westbound toll in Pennsylvania) | ||||||
| Warren | Greenwich Township | 3.94 | 6.34 | 3 | Western end of US 22 concurrency; signed for Route 122/Alpha westbound, Route 173/Bloomsbury signed westbound; last westbound exit before toll | |
| 5.48 | 8.82 | 4 | Warren Glen,Stewartsville | Westbound exit and eastbound entrance; access viaCR 637 | ||
| Franklin Township | 7.03 | 11.31 | 6 | Warren Glen,Asbury,Weigh station | Eastbound exit and westbound entrance; access viaCR 632 | |
| Hunterdon | Bloomsbury | 7.46 | 12.01 | 7 | ||
| Union Township | 11.76 | 18.93 | 11 | CR 614 not signed | ||
| 13.42 | 21.60 | 12 | CR 625/CR 635 not signed | |||
| 15.01– 15.07 | 24.16– 24.25 | 13 | Western end of Route 173 concurrency; westbound exit and eastbound entrance; former routing ofUS 22 | |||
| Franklin Township | 16.06 | 25.85 | 15 | Eastern end of Route 173 concurrency | ||
| Clinton Township | 17.32– 17.87 | 27.87– 28.76 | 17 | Signed as exits 16 (north) and 17 (south) eastbound | ||
| 18.34– 18.53 | 29.52– 29.82 | 18 | Eastern end of US 22 concurrency; US 22/Lebanon not signed westbound | |||
| Lebanon | 20.78 | 33.44 | 20 | Lebanon,Round Valley Recreation Area,Cokesbury | Westbound exit and eastbound entrance; access viaCR 639; signed as exits 20A (Lebanon) and 20B (Cokesbury) | |
| Tewksbury Township | 25.03 | 40.28 | 24 | |||
| Somerset | Bedminster | 27.11 | 43.63 | 26 | FormerCR 523 Spur | |
| 30.80– 30.87 | 49.57– 49.68 | 29 | Exits 21A-B on I-287 | |||
| Bernards–Warren township line | 34.58 | 55.65 | 33 | |||
| Warren Township | 37.39 | 60.17 | 36 | |||
| 40.98 | 65.95 | 40 | ||||
| Watchung | 42.22 | 67.95 | 41 | Berkeley Heights,Scotch Plains | No eastbound entrance; access via Drift Road | |
| Union | Berkeley Heights | 44.01 | 70.83 | 43 | Berkeley Heights,Watchung,New Providence | Access viaCR 655 |
| 44.52 | 71.65 | 44 | New Providence,Berkeley Heights | Eastbound exit and entrance; access viaCR 527 | ||
| Summit | 46.72 | 75.19 | 45 | Eastbound exit and westbound entrance | ||
| Springfield Township | 48.14 | 77.47 | Western terminus oflocal–express lanes | |||
| 49.28 | 79.31 | 48 | Eastern terminus of Route 24; signed for I-287/Springfield/Morristown westbound, Millburn eastbound | |||
| Union Township | 50.58 | 81.40 | 49 | Eastbound exit and westbound entrance; signed as exits 49A (west) and 49B (east) | ||
| 51.43 | 82.77 | 50 | Union Township,Millburn,Maplewood | Westbound exit and eastbound entrance; access viaCR 630; signed as exits 50A (Union) and 50B (Millburn/Maplewood) | ||
| Union Township–Hillside line | 53.11 | 85.47 | 52 | Exits 142A–B on Garden State Parkway | ||
| Hillside | 54.32 | 87.42 | 54 | Hillside,Irvington | Eastbound exit and westbound entrance; access via Winans Avenue | |
| Essex | Newark | 54.88– 55.00 | 88.32– 88.51 | 55 | Hillside,Irvington | Westbound exit and eastbound entrance; access viaCR 602 |
| 56.45 | 90.85 | 56 | West Peddie Street / Elizabeth Avenue –Downtown Newark | Exit from both express and local lanes; no westbound access to West Peddie Street; Downtown not signed eastbound | ||
| 57.23 | 92.10 | 57 | No westbound exit; southern terminus of Route 21 | |||
| 57.45 | 92.46 | No eastbound exit | ||||
| 58.03– 58.32 | 93.39– 93.86 | 58 | Signed as exits 58A (south) and 58B (north); exit numbers not signed westbound; last eastbound exit before toll | |||
| Eastern terminus of local–express lanes | ||||||
| 58.60 | 94.31 | Exit 14 Toll Plaza (western end of Newark Bay Extension) | ||||
| 58.93 | 94.84 | – | Exit 14 on I-95 / Turnpike | |||
| Newark Bay | 60.80 | 97.85 | Newark Bay Bridge | |||
| Hudson | Jersey City | 62.01 | 99.80 | 14A | Access via Port Jersey Boulevard; Route 185 not signed; access toCape Liberty Cruise Port andStaten Island | |
| 64.20 | 103.32 | 14B | Jersey City,Liberty State Park | Access via Bayview Avenue | ||
| 64.50 | 103.80 | Exit 14C Toll Plaza (eastern end of Newark Bay Extension) | ||||
| 64.60 | 103.96 | – | Eastbound exit and westbound entrance; access via Jersey City Boulevard | |||
| 65.50 | 105.41 | – | Columbus Drive | Eastbound exit and westbound entrance | ||
| 66.49 | 107.01 | – | Western end of Route 139 concurrency; westbound exit and eastbound entrance | |||
| 66.76 | 107.44 | Eastern end of freeway section | ||||
| Jersey Avenue (CR 631) –Lincoln Tunnel | ||||||
| 67.03 | 107.87 | Marin Boulevard (CR 637) | ||||
| Hudson River | 67.83 | 109.16 | Holland Tunnel (eastbound toll;E-ZPass ortoll-by-plate) | |||
| Continuation intoNew York at the river's center; eastern terminus of Route 139 | ||||||
1.000 mi = 1.609 km; 1.000 km = 0.621 mi
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