If you've ever been on a boat on the Patapsco near Baltimore, you know what Fort Carroll is. From the water, it looks like a giant concrete bird sanctuary (it certainly smells like one). From the water, it's hard to imagine that Robert E. Lee designed the structure, starting in 1848.

The Fort was part of the first line of defense of Baltimore during the Civil War, but in 1917, guns were removed from the battery at the outbreak of World War I. The army abandoned the fort in 1921, moving all its military equipment to Fort Howard. In 1958, a Baltimore attorney bought the island for only $10,000 with the intention of putting a casino on the island, but plans never came to fruition. This drone footage gives boaters the idea of what the Fort looks like behind its ramparts. It's spooky, and eerie, and completely crazy that nothing is being done to preserve it. The video was posted to YouTube by Greg Cox.