Fort Jefferson in Dry Tortugas National Park, Florida

Fort Jefferson in Dry Tortugas National Park, Florida

Spectacular blue waters, coral reefs and miles of white sandy beaches are all serious draws, but what sets Dry Tortugas National Park apart is the huge relic of Fort Jefferson. Built in the mid-1800s as an outpost for a naval defence of the US Gulf Coast, the fort was never fully completed and abandoned by 1874. In the end, more than 16 million bricks were laid, making it one of the largest forts ever constructed.