6. Utter Inn
The Utter Inn isn’t very glamorous, but it is one of the first underwater structures that is still functioning today. In 2000, a Swedish man by the name of Mikael Genberg built the Utter Inn at Vasteras, Sweden. As a way to make art available to the public. Located a little over 9 feet under the surface of lake Malaren, guests can sleep in the bunker, which has panoramic views of the underwater area. Genberg will even deliver dinner to guests. Reservations book way ahead in advance, and the summer months are the most popular time to stay at the Inn.