Fort Mifflin: The Siege That Saved Washington's Army

Fort Mifflin sits on a small island in the Delaware River just south of Philadelphia, and in the autumn of seventeen seventy-seven it played one of the unsung heroic roles of the Revolutionary War. After the British captured Philadelphia, they needed to clear the Delaware River of American defenses to supply their army by sea. Fort Mifflin stood in the way.

The American garrison held out for weeks under devastating artillery bombardment, one of the most intense of the entire war. They finally evacuated on November fifteenth, seventeen seventy-seven, but the delay they imposed is often said to have given Washington's army crucial time to establish itself at Valley Forge. The fort was rebuilt in the seventeen nineties, with the work supervised at first by Pierre Charles L'Enfant, the designer of Washington D.C., and it served as a United States military post into the twentieth century. Today it is often described as one of the oldest forts in continuous use in the nation.