Deer Island Thoroughfare in Stonington is a heavily traveled coastal navigational passage between Deer Isle on the north and a group of many smaller islands to the south. Located about 22 miles northeast of Rockland, the passage connects Penobscot Bay to the west with Jericho Bay to the east.
Corps’ work in the waterway, completed in 1915, involved excavating rock from an area between Crotch and Moose islands. The rock was removed to a depth of 15 feet over an area 800 feet long and 300 feet wide. This allowed for a channel generally 400 feet wide through the entire thoroughfare.