The remains of a 19th-century isolation hospital for yellow-fever sufferers – and a small cemetery for those who didn’t survive – have been found by archaeological divers on a submerged island in the Dry Tortugas National Park off Key West in Florida.
The discovery was made by US National Park Service (NPS) archaeologists last August during an underwater survey of the sea around Fort Jefferson on the island of Garden Key, a naval station and military prison during the American Civil War. Archival research was carried out before the team were ready to share their findings.
The divers have so far found only a single grave in the cemetery. Its large headstone, inscribed “John Greer, Nov. 5. 1861” is made of a dark sandstone called greywacke, also used as a building material in the fort. According to the records, however, dozens of bodies would have been buried at the site.
Most of these are thought to have been soldiers serving or imprisoned at the fort, but Greer had been a civilian employed as a labourer.
Nowadays an offshore tourist attraction, Fort Jefferson is the Americas’ biggest brick structure, and lies in the Gulf of Mexico 68 miles west of Key West. In 1826 the island, which is surrounded by small sandy islands or keys, provided the site for a lighthouse, but by the time of the Civil War it had been extensively fortified as a strategic military outpost.
Fort Jefferson and the satellite islands were variously used for military training, as a prison, a hospital and as a naval coaling depot.
“This intriguing find highlights the potential for untold stories in Dry Tortugas National Park, both above and below the water,” commented project director Josh Marano, maritime archaeologist for south Florida national parks.
“Although much of the history of Fort Jefferson focuses on the fortification itself and some of its infamous prisoners, we are actively working to tell the stories of the enslaved people, women, children and civilian labourers.”
The numbers of military personnel, prisoners, engineers, support staff, labourers and their families, including enslaved people, grew to the point where outbreaks of the mosquito-borne disease yellow fever killed dozens during epidemics in the 1860s and ’70s.
Small, simple structures had been built on nearby islands for use as quarantine hospitals in an effort to contain the outbreaks.
Fort Jefferson had been largely abandoned by 1874, although between 1889 and 1900 the Marine Hospital Service again located an isolation hospital on one of the islands. Since then many of these islands have shifted, according to the NPS, with climate change and storms causing some to “settle and erode beneath the waves”.
From 1908 the area was declared a federal bird reservation, and in 1992 became part of a protected national park. Visited from Key West, it is said to be popular with scuba divers and snorkellers.