The Southern Tier Expressway is a major highway in the United States, designated as Interstate 86. It runs through the southern part of New York State, connecting the cities of Erie, Pennsylvania, and Binghamton, New York. The expressway spans approximately 150 miles and serves as a vital transportation route for both local and through traffic. Constructed in the 1960s, the Southern Tier Expressway facilitates commerce and travel in the region. It passes through scenic areas, including parts of the Appalachian Mountains, and provides access to various towns and attractions along the way. The highway is essential for economic development and connectivity in the Southern Tier region.