Fort Mifflin on the Delaware (siege-damaged fortifications)

Fort Mifflin, a Revolutionary War–era fort on the Delaware River, was bombarded during the 1777 Siege of Fort Mifflin and suffered heavy damage; the siege and subsequent repairs left portions of its masonry and earthworks in a partly ruined state. Today surviving 18th- and 19th-century walls, bastions, and earthworks remain on the site and are interpreted as historic ruins within a National Historic Landmark.