The Sebasticook River is a 76-mile-long (122 km) river in the central part of Maine, in the United States. From its source (45°03′17″N 69°13′36″W / 45.05480°N 69.22655°W) in Dexter, the upper "Main Stream" section flows generally west and south 30 miles (48 km) to Great Moose Lake. From the outlet of the lake in Hartland, the Sebasticook flows 41 miles (66 km)south to the Kennebec River in Winslow. According to the Sebasticook Regional Land Trust: