Southwest Harbor, Maine was settled in 1761, and incorporated as a town on February 21, 1905, set off from a portion of Tremont.
The town is located on the southwest entrance to Somes Sound, diagonally across from Northeast Harbor, a village within the town of Mount Desert. Since its earliest days as a town, Southwest Harbor has been both a fishing village and resort community.
Maine Route 102 begins at the entrance to Mount Desert Island, and loops to the main village of Southwest Harbor, turns to Bass Harbor in Tremont, and returns toward Somesville.