The Sagadahoc Bridge is a four-lane concrete segmental box girder bridge between the City of Bath and the town of Woolwich, Maine, carrying U.S. Route 1 (US 1) over the Kennebec River. It was completed in 2000 to replace the two-lane road portion of the adjoining 1927 Carlton Bridge, which remains in use as a rail bridge. It is 2,972-foot-long (906 m) and features the longest precast concrete segmental span in North America at 420 feet (130 m). It is also notable for being the first design/build project undertaken by the Maine Department of Transportation. The bridge cost $46.6 million, and is the last downstream road crossing of the Kennebec.