High Quality Content by WIKIPEDIA articles! Route 3 is a southward continuation of U.S. Route 3, connecting Cambridge, Massachusetts with Cape Cod. All of it, except for the northernmost end in downtown Boston and Cambridge, is a freeway. The section from Boston to Braintree is also marked as Interstate 93 and U.S. Route 1 and is known in downtown Boston as the Central Artery, and south of downtown as the Southeast Expressway. In Braintree, I-93 and US 1 split to follow the Yankee Division Highway to Interstate 95, and Route 3 continues south on its own, as the Pilgrims Highway. This section extends to a junction with U.S. Route 6 in Sagamore, just before the Sagamore Bridge over the Cape Cod Canal where Route 3 originally ended at rotary. Replacement of this rotary with a grade- separated interchange was completed in November 2006. Because Route 3 and U.S Route 3 are treated as the same route by the Massachusetts Department of Transportation (MassDOT), mileposts increase continuously from Bourne to the New Hampshire border.