Fort Mifflin on the Delaware is a historic military installation in Philadelphia built in 1771 on Mud Island in the Delaware River. Originally called Fort Island Battery, it was renamed in 1777 after Thomas Mifflin, a major general in the Continental Army. The fort achieved historic significance during the American Revolution when British forces unleashed over 10,000 cannonballs in the greatest bombardment of the war, with nearly 350 Americans killed in November 1777. Today a National Historic Landmark, Fort Mifflin remains the oldest fortification continually used in the United States and offers guided tours, school field trips, and living history programs depicting its Revolutionary War heritage and strategic importance to American independence.
