Part of the national historic area, this coastal battery was known to the military as Hill 400 or colloquially as Little South America (due to its shape). The hill was fortified with 155mm guns, ammunition magazines, water tanks, 22 Quonset huts and a concrete command post at the top. You can easily hike to the peak of Bunker Hill along a gravel road picked up just after crossing the bridge to Amaknak Island.