Most people book their accommodations at pretty hotels with excellent customer service and quality amenities. For some, they're willing to splurge just to sleep in comfy queen-size beds, eat at lavish restaurants or swim in Olympic-size pools.

But did you know there are also hotels in the world that sell because of these qualities? These hotels have certain types of peculiarities open-minded travelers will experience. Here are some of the most unusual hotels in the world:

The Dog Bark Park Inn, Idaho, USA is an unusual bed and breakfast in Idaho is dog-friendly. Literally. The whole building is shaped like a beagle, where guests can stay inside through the beagle's body. It is owned by chainsaw artists Dennis and Frances, and once you're inside, you'll be treated with several more wooden carvings of dogs scattered all over the guesthouse. It would be nice to say that you've slept inside a dog in your life. So go over to Idaho and check the place out.

If you're not claustrophobic, then you can definitely check out the Aydinli Cave House Hotel, Goreme, Turkey, which is located inside a cave. The Aydinli Cave House Hotel will give you a complete cave experience, minus the actual caveman living, of course! All basic amenities are offered here, and all its 14 rooms are decorated naturally to preserve the essence of the cave. This hotel started serving guests in 2008, where tourists can enjoy the Turkish culture whilst inside a natural cave with structures dating back to over 750 years.

Located 200 km north of the Arctic Circle, guests of Icehotel, Jukkasjarvi, Sweden can come any day of the year to have the ultimate Ice experience, where all amenities are made of ice. This isn't just a normal room chipped out of huge blocks of ice. You can stay at luxury suites and art suites in this place-complete with an ice bar and an ice gallery. Brave the freezing cold and stay at the world's only ice-themed hotel!

Treehotel, Harads, Sweden. Another unusual hotel found in Sweden is the Treehotel, where guests can stay in futuristic treehouses. All rooms are ecological-friendly, but all needs are well taken care of and of the highest quality. Each treehouse also has its own theme, whether you want to stay in a bird's nest, flying saucer, and several other choices. If you want to sleep in a high-standard accommodation while perched on top of the trees, make a reservation now.