Philadelphia’s Fort Mifflin—the oldest American fort in continuous service—faced the biggest test of its more-than-175-year U.S. military career in late 1777. During the Revolutionary War’s Philadelphia campaign, the earth and palisade strongpoint on the Delaware River withstood the mighty Royal Navy for six days, enduring the most ferocious bombardment of the war.
The fort was originally located on Mud Island, now part of the river’s west bank, near the confluence of the Delaware and the Schuylkill River. Construction began in 1771 and proceeded slowly until the outbreak of the Revolution. Finally in 1777, workers, militiamen, and Continental soldiers hastily finished the fort, which consisted of a rampart facing the river and a palisade protecting its landward sides.
The importance of Fort Mifflin, then known as Fort Island or Fort Mud, vastly increased when British troops occupied Philadelphia, then several miles upriver, on 27 September 1777. The British needed to clear the Delaware in order to supply their troops in the city. In addition to Mifflin, other nearby American defenses included a fort at Billingsport, about three miles downriver; Fort Mercer, across the river at Red Bank, New Jersey; several hastily emplaced batteries along the shoreline; and hundreds of underwater obstructions. A type of chevaux-de-frise, each featured stout iron-tipped beams capable of puncturing a ship’s hull. Fort Mifflin was also the base for an assortment of Pennsylvania State Navy vessels.
In late September, the Royal Navy began operations against the defenses, slowly advancing upriver. Upon arriving opposite forts Mifflin and Mercer in early November, the invaders first attacked the latter, believing it to be lightly defended, but were repulsed with heavy casualties. The British then turned their attention to Fort Mifflin. On 10 November, British warships commenced the heaviest artillery bombardment of the Revolutionary War. During the ensuing siege, the garrison’s ammunition ran so low that one of the defenders, Joseph Plumb Martin, wrote in his diary that a dram of rum was offered for each British cannonball recovered, which could then be fired back at the enemy.
On the 15th, blasts from British land batteries augmented the naval fire, devastating the fort. That night, the soldiers who had survived the bombardment escaped across the river to Fort Mercer. The gallant defense of Mifflin had delayed the British, helping to prevent them from attacking General George Washington’s worn-out army before the opposing forces settled into winter quarters.
The fort continued to serve as an important American defense after the Revolutionary War. In 1795 it was enlarged and strengthened. Three years later its name was changed to Fort Mifflin, in honor of Pennsylvania Governor Thomas Mifflin, who had served as quartermaster general of the Continental Army. Between 1780 and 1800, 50% of the young United States’ coastal defense funds were allocated to the Philadelphia outpost. Eventually, in 1954, the U.S. government turned the fort over to the city.
Fort Mifflin is presently in its post-Revolutionary War configuration. Visitors can observe the rough conditions under which early 19th-century soldiers lived by visiting their brick barracks. The building also contains several historical displays, including a large diorama of the defense of the Delaware River. Local and state grants are funding the restoration of the fort’s citadel, which later became the commandant’s house. Other structures include an artillery shed, officers’ quarters, quartermaster’s store, arsenal, and blacksmith’s shop.
Knowledgeable guides in period dress are available to conduct tours, but please call in advance to make arrangements. The fort is reportedly one of the most haunted places in Philadelphia, with at least six ghosts prowling its buildings and ramparts. Visitors may be lucky enough to glimpse one of the apparitions during Mifflin’s ghost tours, which are conducted on Thursday nights during October.
While the city of Philadelphia owns the historic landmark, a not-for-profit organization, Fort Mifflin on the Delaware, operates it and depends on admission fees, donations, and community service to maintain it. The fort is located just south of the Philadelphia Naval Base and just north of the Philadelphia International Airport, and is open Wednesday-Sunday, 10 a.m.- 4 p.m. Admission is $6 for adults, $3 for children under 12 (children under 5 are free), $5 for senior citizens, and $3 for active military personnel or veterans.
For more information, call Fort Mifflin at (215) 685-4167 or visit its website at www.fortmifflin.com.