Interstate 87 (I-87) is a 333.49-mile-long (536.70 km) 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.