On the German island of Rügen in the Baltic Sea is the world’s largest hotel. The hotel is so big that it covers about three miles and has 10,000 bedrooms that all face the sea, however, despite being built about 70 years ago, it has never seen a guest staying over. It was named Prora and has been built by Nazis between 1936 and 1939 upon Hitler’s orders. The building project was left unfinished owing to Hitler’s commitment to war.