U.S. Highway 20 travels the length of state of Massachusetts, from Boston to the Berkshires. It begins along the original route of the Upper Post Road, an alternate to the first or Old Post Road that traveled between Boston and Hartford. Explore over 200 historic sites and landmarks across The Bay State. The link is available at autotrails.net.
American Auto Trail-Massachusetts’ U.S. Highway 20 is now on Google Maps
Historic Highway Guides 