Fort Mifflin

Fort Mifflin

Philadelphia, Pennsylvania 19104, United States

Created By: PocketSights

Tour Information

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.

Tour Map

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What You'll See on the Tour

Main Gate

Massive entrance doors and arch on northeast riverside. The gate flanked by massive stone quoining and brick jamb supports. The arch has a head stone dedicated, to President Adams. The doors are heavy wood planks with cast iron straps, bolt... Read more
Guard House (Arsenal)

Built in 1815 to 1816, the guard house displays unusual fenestration and sophisticated detailing. By 1839 it was designated as an arsenal.
The Soldiers Barracks

Built in the 1790s, the soldiers barracks is one of the larger structures of the fort and a fine example of early barracks structure.
Officers' Quarters

Built in 1814, the officer's quarters are typical of Fort Mifflin construction, yet embellished with ornamental woodwork and ironwork. Officers and their families lived in this building, with the exception of the commandant. The conditions ... Read more
Blacksmith Shop

Built before 1802, the smith's shop may be the oldest structure of the fort. Even though the grounds at Fort Mifflin could not accommodate horses, the blacksmith was still quite busy. In most cases, the blacksmith working at the Fort was a ... Read more
Artillery Shed

Built in 1837, the artillery shed was used for the storage and protection of cannon on an interior raised platform.
The Commandant's House

This building served as both the Citadel, or fort within a fort, for the Fort and as the living quarters for the Commandant and his family. The upstairs included living quarters for the family, while downstairs was an office, kitchen, and a... Read more


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