Interstate 87 (I-87) is a north–south Interstate Highway located entirely within the US state of New York. I-87 is the main highway that connects New York City and Montreal. The highway begins at exit 47 off I-278 in the New York City borough of the Bronx, just north of the Robert F. Kennedy Bridge. From there, the route runs northward through the Hudson Valley, the Capital District, and the easternmost part of the North Country to the Canada–United States border in the town of Champlain. At its north end, I-87 continues into Quebec as Autoroute 15 (A-15). I-87 connects with several regionally important roads: I-95 in New York City, New York State Route 17 (NY 17; future I-86) near Harriman, I-84 near Newburgh, and I-90 in Albany. The highway is not contiguous with I-87 in North Carolina.
I-87 was assigned in 1957 as part of the establishment of the Interstate Highway System. The portion of I-87 south of Albany follows two controlled-access highways that predate the Interstate Highway designation, the Major Deegan Expressway (locally known as "the Deegan") in New York City and the tolled New York State Thruway from the New York City line to Albany. North of Albany, I-87 follows the Adirondack Northway, a highway built in stages between 1957 and 1967 (finished just in time to bring Americans to the World Exhibition held in Montreal that year). Early proposals for I-87 called for the route to take a more easterly course through the Hudson Valley and extreme southwestern Connecticut between New York City and Newburgh. These plans were scrapped in 1970 when I-87 was realigned onto the Thruway between Westchester County and Newburgh.
Route description I-87 makes up most of the major strategic corridor between New York City, the largest metropolitan area in the US, and Montreal, the second-largest metropolitan area in Canada (formerly the largest). The New York State Department of Transportation (NYSDOT) considers the route important for commerce, as it connects with numerous highways in the region and serves approximately 80 million people in the Mid-Atlantic states, New England, and Quebec. Motorists can connect to multiple highways to travel farther south along I-95 through the Mid-Atlantic states or farther east into New England.
South of Albany
Major Deegan Expressway
I-87 and the Major Deegan Expressway begin in the Bronx at the northern approach to the Robert F. Kennedy Bridge, where it connects to the Bruckner Expressway (I-278) at a directional T interchange. The route heads west from the interchange, paralleling loosely with the Harlem River through Mott Haven. After , the highway makes a turn to the north, mirroring a change in the nearby river's course. It passes by Yankee Stadium on its way to Highbridge, where the Deegan connects to the Cross Bronx Expressway (I-95 and US Route 1 [US 1]) at the eastern approach to the Alexander Hamilton Bridge. The Deegan remains in close proximity to the Harlem River until the waterway turns westward at Kingsbridge to form the northern edge of Manhattan. The Major Deegan Expressway is named after Major William Francis Deegan.
North of Kingsbridge, the expressway follows a generally northeasterly alignment, passing through the center of Van Cortlandt Park as it connects to Mosholu Parkway and Jerome Avenue. Mosholu Parkway also links the Deegan to the Henry Hudson and Saw Mill River parkways, which run parallel to the Major Deegan Expressway through the western Bronx and Manhattan. Past Jerome Avenue, the freeway gains a pair of service roads and heads north to the New York City line, where it becomes the New York State Thruway as it passes into Westchester County. The last northbound exit on the Deegan connects to McLean Avenue, located north of the city line in Yonkers. The exit 14 ramp leads to the service road in the Bronx but does not meet McLean Avenue until it crosses the county line. Southbound access to McLean Avenue is provided by Thruway exit 1 in Yonkers.
New York State Thruway
At the New York City–Yonkers border, I-87's mainline continues onto the New York State Thruway and northward through Yonkers and southern Westchester County. The mile markers and exit numbers reset at city limits where the Major Deegan Expressway becomes the Thruway. The first few exits serve various local streets, with exit 1 serving Hall Place, exit 2 providing access to Yonkers Raceway & Empire City Casino and exit 3 serving the Cross County Shopping Center. At exit 4, I-87 connects to the Cross County Parkway, an east–west parkway providing access to the Saw Mill River, Bronx River, and Hutchinson River parkways. The north–south parkways and I-95 run parallel to the Thruway through Southern Westchester. The Bronx River parkway leaves to the northeast midway through Yonkers, while the Saw Mill and Sprain Brook parkways follow the Thruway out of the city.
All three highways take generally parallel tracks to Elmsford, where I-87 directly intersects the Saw Mill River Parkway at exit 7A. Not far to the north is exit 8, a semi-directional T interchange with I-287 (the Cross Westchester Expressway). I-287 joins the Thruway here, following I-87 west across the Hudson River into Rockland County on the Tappan Zee Bridge. I-87 and I-287 remain overlapped for through the densely populated southern portion of Rockland County, meeting the Palisades Interstate Parkway and the Garden State Parkway Connector, with the latter providing access to the Garden State Parkway in New Jersey. The Thruway continues generally westward to Suffern, where I-87 and I-287 split at a large semi-directional T interchange (exit 15) only about a half mile () from the New Jersey border. At this point, I-287 heads south into New Jersey while I-87 and the Thruway turn northward into the valley of the Ramapo River.
The Thruway continues north as a six-lane tollway through the river valley toward Harriman, where it encounters the Woodbury toll gantry, the southeastern end of the main line's major closed toll system. The barrier is located on the mainline within exit 16 (NY 17), a trumpet interchange. Along with the mainline barrier in Harriman, a toll gantry exists on the exit 16 ramp midway between the Thruway and NY 17 exit 131 (NY 32). Now a completely tolled highway, the Thruway heads northward as it narrows to four lanes, roughly paralleling the Hudson River to the river's west as it serves the city of Newburgh, village of New Paltz, and city of Kingston, indirectly connecting to the short I-587 in the latter.
Past Kingston, the highway goes closer to the river as it parallels US 9W through the towns of Saugerties, Catskill, Coxsackie, and Ravena. Just north of Ravena, the Thruway meets the west end of the Berkshire Connector, a spur linking the Thruway mainline to the Massachusetts Turnpike to the east. The highway continues into the vicinity of Albany, where it connects to Troy via I-787 at exit 23 and intersects I-90 at exit 24. The latter of the two junctions is the busiest of the Thruway's exits, serving an estimated 27 million vehicles a year. I-87 then widens to six lanes and runs across the capital city's residential suburbs for to exit 24, a complex interchange with I-90. Traffic intending to either continue on I-87 or reach I-90 east must exit the Thruway here. At this point, I-87 leaves the Thruway to access the nearby south end of the toll-free Adirondack Northway, also known simply as the Northway, while I-90 merges in from the east to follow the Thruway toward Buffalo and then Pennsylvania.
Adirondack Northway Off the Thruway, I-87 and I-90 overlap for a half mile () along I-90's toll-free path through the Albany area. The brief concurrency ends at exit 1 of the Adirondack Northway in Guilderland, a junction also numbered as exit 1 on I-90. The Adirondack Northway and I-87 are still separate routes that share the same path; the Northway itself actually begins not at I-87/I-90 but about south from its interchange, the Northway reaches its southern terminus at Western Ave (US 20), and then joins with I-87 for the rest of its route. I-87 turns to head north toward the Canada–United States border at Champlain while I-90 continues east toward downtown Albany and Rensselaer County. South of this point, the Northway feeds into a expressway spur known locally as Fuller Road Alternate, which links I-87 and I-90 to US 20. Fuller Road Alternate is designated as New York State Route 910F (NY 910F), an unsigned reference route, by NYSDOT. In 2004, NYSDOT ceremonially designated the entire Northway as the Adirondack Veterans Memorial Highway.
The Northway, the part of Interstate 87 (I-87) north of the New York State Thruway, was built in segments, which became I-87 as they were completed and linked to the pre-existing route. Construction began in the late 1950s on the portion of the Northway between the Thruway and NY 7 near Latham, and it was completed in 1960.
Albany and Saratoga counties I-87 heads northeast from I-90 as a six-lane freeway with three lanes in each direction. It immediately traverses the Albany Pine Bush Preserve and passes west of Rensselaer Lake before crossing CSX Transportation's Hudson Subdivision and running parallel to Wolf Road, a business thoroughfare through the town of Colonie. Wolf Road itself begins adjacent to exit 2, a cloverleaf interchange with NY 5 (Central Avenue). Heading northbound, the ramp for exit 2E feeds directly into the intersection of NY 5 and Wolf Road, located just west of Colonie Center, one of the Capital District's largest enclosed shopping malls. I-87 continues to run alongside Wolf Road to exit 4, a modified diamond interchange serving County Route 151 (CR 151, named Albany Shaker Road) and Albany International Airport. Wolf Road ends south of the exit; however, another section begins north of the junction, carrying NY 155 away from the airport. Prior to the Northway, there was no break in Wolf Road; in essence, exit 4 was built on top of Wolf Road's intersection with Albany Shaker Road. I-87 and NY 155 meet at exit 5, with the latter routed along Watervliet Shaker Road.
After a brief stretch of housing tracts, I-87 connects to NY 2 and NY 7 at exit 6, a single-point urban interchange, in a commercialized part of Latham. NY 7 joins I-87 here, following the freeway for roughly to exit 7, the west end of a limited-access highway previously known locally as Alternate Route 7. While NY 7 heads east toward Troy, I-87 continues north past gradually less commercialized areas as it approaches the northern county line. The businesses ultimately give way to stretches of homes and subdivisions as the highway crosses into Saratoga County by way of the Thaddeus Kosciusko Bridge, called by locals "the twin bridges", spanning the Mohawk River. The northern portion of the Northway through Colonie and Saratoga County is now a heavily traveled commuter route as a six-lane freeway. Since the highway's construction, Saratoga County has become the fastest growing area of the Capital District, and indeed all of upstate New York.