Battery Steele, located on the former Peaks Island Military Reservation on Peaks Island, in Portland, Maine represents the most advanced form of Coastal Defense installation developed by the United States Army during World War II. Due to its location as an outer island in the bay with a clear view across the North Atlantic, Peaks Island was chosen as the principal site for Casco Bay?s defensive system. The battery was armed with two 16? guns capable of firing a 2000 pound shot 26 miles to sea. These were the largest, land based guns in the history of American Coastal Defenses, and represents the final development in the 170 year history of defending the Port of Portland and Casco Bay from naval attack. Battery Steele was one of forty-three planned primary gun installations of this size, however by the end of the war only 23 were completed and of these, only 17 were armed. Although the guns, shields, carriages and accompanying controls were destroyed or removed after the war, Battery Steele remains otherwise intact. It is an important relic of the end stage of American efforts to mount land based coastal defenses.