Fort Jefferson began life just before the Civil War. It saw service as a Union outpost during it, as a prison after it, and as supply depot at various times before, during and after. But, even though they kept trying, it was never finished. And honestly no one seemed to want to be there. (Imagine wearing a wool uniform here int the summer.) That might be a reason why it wasn’t finished.

Now it is a crumbling, but beautiful reminder of a bygone time. And it protects not the nation, but a wildlife refuge that desperately needs it.