The only park in the National Park System to serve as a memorial to all Americans ever held as prisoners of war, this unique historic site was officially known as Camp Sumter and was the largest of the many Confederate military prisons that were established during the Civil War. During the 14 months it existed, more than 45,000 Union soldiers were confined here. The park has three main features, the National Prisoner of War Museum, the historic prison site, and the National Cemetery.