Fort Delaware (Pea Patch Island, New Castle County, Delaware)
Pea Patch Island, New Castle County · Delaware · Civil War
History & Significance
Fort Delaware was built on Pea Patch Island, a marshy location in the Delaware River that emerged in the 18th century and received its name from a legendary cargo of peas. Following unsuccessful fortification attempts during the War of 1812 and a devastating fire that destroyed an earlier star fort in 1831, the present masonry structure was erected between 1848 and 1860 under chief engineer Joseph Gilbert Totten.
Designed as a coastal defense facility to shield Philadelphia and Wilmington from naval attack, the fort was completed and modernized with advanced Third System fortification technology. However, its primary historical significance stems from its Civil War service as a Union prisoner-of-war camp.
Beginning in 1862, the fort housed thousands of captured Confederate soldiers, including many taken at Gettysburg. At peak capacity in 1863, over 12,500 prisoners were confined on the island in wooden barracks and within the fort itself.
Although conditions were harsh—marked by poor drainage, overcrowding, and disease—Fort Delaware maintained one of the lowest mortality rates among Civil War prisons, with approximately 10 percent of prisoners dying versus much higher rates at notorious camps like Andersonville. The fort remained garrisoned through World War II before being declared surplus in 1944. In 1951, Fort Delaware became one of Delaware's first state parks, operated as a living history museum and National Register site.
Key Facts
Map
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🧳 Visiting
What you’ll see when you visit:
- Pentagonal masonry fort with casemates and gun positions dating to 1848–1860
- Civil War-era prison camp that held nearly 33,000 Confederate detainees
- Preserved barracks and period structures on Pea Patch Island in the Delaware River
- Living history exhibits and demonstrations interpreting military and prison camp operations
Sources
- https://en.wikipedia.org/wiki/Fort_Delaware
- https://en.wikipedia.org/wiki/Fort_Delaware_State_Park
- https://www.destateparks.com/park/fort-delaware/
- https://www.loc.gov/item/de0129/
- https://www.battlefields.org/visit/heritage-sites/fort-delaware-state-park
- https://delawarestateparks.blog/2020/05/04/history-of-pea-patch-island/
- https://news.delaware.gov/2026/04/16/unveiling-of-new-state-historical-marker-honoring-fort-delaware/
- https://www.hmdb.org/m.asp?m=21589