Here is another from the historic Fort Jefferson in the Dry Tortugas National Park. This is inside one of the many incredible hallways.
It is so amazing that they could have built this place 170 years ago, on an island 70 miles from any civilization Well... At that time there were no bridges fastening the keys to the mainland, so it was probably more like 200 miles from civilization. They had to transport all those bricks all the way out there. Amazing that they could lay these bricks so perfectly straight and symmetrical without the aid of any power tools or computer programs.
Even more amazing that 170 years later, after being pounded by countless hurricanes, that is could still look this perfect, level, and well preserved today. You would think that the weight of all those bricks would have sunk into the soft sand by now and the place would crumble.