The world's weirdest hotels?

1. Knock on wood! Stay in a tree... Hotel Norrqvarn in Sweden has two hotel rooms in a tree
2. Cool! Stay in a room made of ice. Sleep on a bed made of ice in the Icehotel in Sweden
3. Choose the Flying bed room and fly into you hotel room in Berlin, Germany 
4. A $500 hotelroom without a toilet? Yes, in an old factory on Gotland island, Sweden Strange but luxury design in this Italian hotel for design lovers , Italy
5. Check in at a design Convent hotel on Mallorca, Spain
6. Have you seen this French bizarre 'hamster hotel'. You can run inside a wheel in France.
7. Totally Pink! Germany’s first Barbie-themed hotel room. Bring your pink suitcase and pink sun glasses.
8. Sleep in a dog house in Idaho, US.
9. A Trojan Horse suite in France
10. The airplane suite, stay in an aircraft in the Netherlands. "From your airplane suite, you will have a fantastic view of the platform and runway at Teuge airport"
11. Feel like an Indian and check into the Wigwam hotel in Arizona.
12. Placia del Sal in Bolivia is a hotel made of salt.
13. Swiss nuclear bunker converted into a eco-luxury hotel. Sounds nice doesn´t it? The Null Stern Hotel in Teufen, Switzerland.
14. The Dockside Crane Hotel is a dockside crane converted into a luxury hideaway for two in Harlingen Netherlands. The view is fab!
15. Das Park Hotel in Ottensheim, Austria. A Bed & Breakfast built from giant concrete sewage pipe segments. I hope they cleaned them well before the put in the furniture...

Have I missed any weird hotel that should be added to the list? Please let me know by leaving a comment here.