Interstate 90, the Massachusetts Turnpike, leads west from Boston to the Berkshires. The main north–south road within the Berkshires is U.S. 7. Highway 2 runs from the northern Berkshires to Greenfield at the head of the Pioneer Valley and continues across Massachusetts into Boston. The scenic section of Highway 2 known as the Mohawk Trail runs from Williamstown to Orange. Interstate 91 runs north–south in the Pioneer Valley in Western Massachusetts.