Interstate 79 is an Interstate Highway in the United States. It goes from Charleston, West Virginia north to Erie, Pennsylvania. The route is long. It is a primary thoroughfare through western Pennsylvania and West Virginia. It is also an important corridor to Buffalo, New York, and the Canadian border. From Sutton north, Interstate 79 generally parallels the path of U.S. Route 19. With the exception of the area between Washington and Cranberry Township, Pennsylvania, I-79 functionally replaces U.S. Route 19.