Tortugas Harbor Lighthouse, Fort Jefferson, Dry Totugas NP, FL; 25-ft tall cast iron hexagonal pyramid tower, 25-ft tall tower, circa 1876, dry tortugas lighthouse, Dry Tortugas NP, FL, Florida, fourth order, Garden Key, Garden Key Lighthouse, Garden Key/Fort Jefferson Lighthouse, Lighthouse, mariner's aid, nautical aid, out of commission, out of service, Tortugas Harbor Lighthouse