Fort Warren - History and Facts | History Hit

Fort Warren

Hull, Massachusetts, United States

Fort Warren on George’s Island in Boston was a fortification built during the American Civil War.

Antara Bate

24 Nov 2020
Image Credit: James Kirkikis/

About Fort Warren

Fort Warren on George’s Island in Boston was built by the Union during the American Civil War as a defensive structure. It was one of the ‘Third System’ plan forts intended to defend the seacoast.

Fort Warren history

Construction of Fort Warren began in 1833, and was not completed until 1861. Unfortunately, by this time, the fortifications of Fort Warren were obsolete, rendering it useless for its intended purpose.

Fort Warren was designed by Sylvanus Thayer, who also designed Fort Independence on Castle Island. Thayer named the fort for Major-General Joseph Warren, a renowned Revolutionary War hero who was killed in the Battle of Bunker Hill. The fort’s design includes a five-point bastion system which was constructed using hand-shaped granite blocks from Quincy and Cape Ann, Massachusetts.

As it was no longer suitable for its original purpose, Fort Warren went on to become a prison for Confederate prisoners of war as well as a training facility.

James M. Mason and John Slidell, the Confederate diplomats seized in the Trent affair, were among those held at the fort. Military officers held at Fort Warren include Richard S. Ewell, Isaac R. Trimble, John Gregg, Adam “Stovepipe” Johnson, Simon Bolivar Buckner, Sr., and Lloyd Tilghman. Prominent civilians held at Fort Warren include Confederate Vice President Alexander H. Stephens, and Confederate Postmaster General John Henninger Reagan. The prison camp had a reputation for humane treatment of its detainees.

It was finally decommissioned in 1947. Today, Fort Warren is part of Boston Harbour Islands National Park, which offers guided tours of the site.

Fort Warren today

Fort Warren is a National Historic Landmark and a major tourist attraction at Boston Harbor Islands. George’s island is visited by more than 100,00 people annually, including those visiting the fort and using the island as an access point to the other islands.

During the off season, the National Park Service brings Boston area schoolchildren to Fort Warren to learn about the fort’s construction, harbour defence and maritime history. Visitors can experience this when walking around the fort and can view the fort’s hospital, bakery and hallways where the ghost of the “Lady in Black” is rumoured to haunt.

The star-shaped fort features granite archways and stairways that open up to the fort roof, which provides panoramic views of the Boston skyline and Massachusetts Bay. Georges Island also contains overlooks and beaches, making it a destination for picnics and swimming.

Getting to Fort Warren

Located seven miles from downtown Boston, Fort Warren is accessible by public ferry or private boat. Transfers are then available for those who wish to visit some of the other Harbor Islands.

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