Carlton Bridge, Railway bridge in Sagadahoc County, US

Carlton Bridge is a railway crossing with a vertical-lift mechanism that spans the Kennebec River between Bath and Woolwich. The movable section can raise to allow boats to pass, while the lower deck continues to serve freight trains to local manufacturers.

Completed in 1927, the Carlton Bridge carried one rail line and two lanes of U.S. Route 1 over the Kennebec River between Bath and Woolwich. On August 1, 2000, the highway was transferred to the adjoining Sagadahoc Bridge and the road connection was severed at the west end. The east end is now gated and open only to authorized vehicles.

The east end of the Carlton Bridge is gated and open only to authorized vehicles, so the deck cannot be walked by the public. Since US 1 moved to the Sagadahoc Bridge in 2000, the bridge's main traffic has been freight trains of the Cumberland and Knox Railroad heading to manufacturers in Thomaston, several passing each week.

The structure today serves active freight operations, with the upper deck no longer offering public road access. Best views come from the river banks or nearby roads in Bath and Woolwich rather than from crossing the bridge directly.

The bridge is the last downstream fixed crossing of the Kennebec. Since US 1 moved to the Sagadahoc Bridge in 2000, its main traffic has been Cumberland and Knox Railroad freight trains bound for manufacturers in Thomaston, several passing each week.