U.S. Route 3 is a north-south highway that runs through the northeastern United States. It stretches approximately 160 miles, connecting the city of Portsmouth, New Hampshire, to the town of Cambridge, Massachusetts. The route primarily serves as a vital link for local traffic and regional travel. Established in the 1920s, U.S. Route 3 is part of the U.S. Highway System. It passes through several towns and cities, including Concord and Nashua, providing access to various attractions and services. The highway plays an essential role in facilitating commerce and tourism in the region.