 New York State Route 100A | ||||
|---|---|---|---|---|
 Map of Westchester County in southeastern New York with NY 100A highlighted in red | ||||
| Route information | ||||
| Auxiliary route ofNY 100 | ||||
| Maintained byNYSDOT | ||||
| Length | 4.21 mi[1] (6.78 km) | |||
| Existed | 1930[citation needed]–present | |||
| Major junctions | ||||
| South end |  NY 100 inHartsdale | |||
| Major intersections |  I-287 inElmsford | |||
| North end |  NY 100 /NY 100C at theGreenburgh–Mount Pleasant line | |||
| Location | ||||
| Country | United States | |||
| State | New York | |||
| Counties | Westchester | |||
| Highway system | ||||
| ||||
New York State Route 100A (NY 100A) is a 4.21-mile (6.78 km) loop route ofNY 100 inWestchester County, New York, in the United States. It follows West Hartsdale Avenue and Knollwood Road in the town ofGreenburgh. The route starts in the hamlet ofHartsdale and ends in the community of Grasslands at the boundary between the towns of Greenburgh andMount Pleasant.
NY 100A begins at an intersection withNY 100 (Central Park Avenue) in the town ofGreenburgh, a short distance north ofHartsdale. NY 100A winds northwest through the hills of Greenburgh as West Hartsdale Avenue, passing multiple residences on its way up. Just after Woods End Lane, the route turns northward through Greenburgh, passing Ridge Road County Park and the Metropolis Country Club before reaching a junction withNY 100B (Dobbs Ferry Road). At this junction, NY 100A changes monikers to Knollwood Road, winding northward through Greenburgh into a junction withNY 119 as it crosses into the village ofElmsford.[2]
After NY 119, NY 100A passes Yosemite Park and enters exit 4 off theCross Westchester Expressway (I-287). NY 100A continues northeast through Elmsford, running along the southeastern edge of the Knollwood Country Club and passing an entrance toWestchester Community College. After passing the entrance, the route winds northward through Greenburgh, passing multiple residences before reaching a junction with NY 100 (Grasslands Road) andNY 100C (Grasslands Road) just east of theSprain Brook Parkway. This junction marks the northern terminus of NY 100A and the eastern terminus of NY 100C, with NY 100 turning north onto Bradhurst Avenue, the continuation of Knollwood Road. Several blocks away from this junction is theKensico Cemetery.[2]
NY 100A was designated in the1930 state highway renumbering and has not had any major changes since.
The entire route is inWestchester County.
| Location | mi[1] | km | Destinations | Notes | |
|---|---|---|---|---|---|
| Hartsdale | 0.00 | 0.00 | NY 100 (Central Park Avenue) | Southern terminus | |
| Greenburgh | 1.52 | 2.45 |  NY 100B (Dobbs Ferry Road) | ||
| Elmsford | 2.21 | 3.56 |  NY 119 –Elmsford | Interchange | |
| 2.33 | 3.75 | I-287 | Exit 4 on I-287; formerI-487 | ||
| Greenburgh–Mount Pleasant line | 4.21 | 6.78 |    NY 100 /NY 100C west toSprain Brook Parkway | Northern terminus; eastern terminus of NY 100C | |
| 1.000 mi = 1.609 km; 1.000 km = 0.621 mi | |||||
