Hrad Loket

You're standing at Loket Castle, in the Czech town of the same name. Take a look around. The castle sits on a massive rock, and the Ohře river wraps around it on three sides. That tight bend gave the place its old German name, Elbogen, which means elbow. Thanks to its thick walls, it was once called the impregnable castle of Bohemia, and it's one of the oldest stone castles in the country.