Bass Harbor Bar in Tremont lies between the southern tip of Mount Desert Island and Great Gott Island. The bar is immediately east of Bass Harbor.

In 1913 the Corps completed a channel through the bar that clears a passage between Blue Hill Bay to the west and the Atlantic Ocean to the east. The project was constructed to provide fishing vessels, recreational craft, and other coastal traffic with a safer, shorter route around Mt. Desert Island. The channel, located about 1,000 feet south of Bass Harbor Head Lighthouse, is 14 feet deep and 250 feet wide.