Fort Mifflin

Fort Mifflin, originally called Fort Island Battery and also known as Mud Island Fort, was commissioned in 1771 and sits on Mud Island (or Deep Water Island) on the Delaware River below Philadelphia, Pennsylvania near Philadelphia International Airport.

Three hundred and fifty American soldiers died defending Fort Mifflin in November 1777. This fort, which withstood the heaviest bombardment of the American Revolution, was rebuilt and housed prisoners during the Civil War. After decommissioning in 1962, Fort Mifflin was given to the City of Philadelphia and portions of the fort were restored and preserved over time. The U.S. Army Corps of Engineers still uses Fort Mifflin, making the fort the oldest active military base in the United States, and the only base older than the Declaration of Independence.