Located within the Arctic Circle, deep in the snowbound Saariselka area of northern Finland, the cabins are built from ice or glass; both are surprisingly warm, but somewhat lacking in privacy.
Courtesy kakslauttanen.fi
Dog Bark Park Inn (United States) —
Shoo, Snoopy. There's a new beagle in town.
courtesy dog bark park inn
The Dovecote (UK) —
The former real dovecote, which fell into disrepair in the early 20th century, has been restored and converted into a cozy self-catering place that can sleep up to four people.
Courtesy The Dovecote
Adrere Amellal (Egypt) —
This extraordinary eco-lodge, built from salt rock and mud, sits in the middle of the Saharan oasis at Siwa, eight long, dusty hours' drive from Cairo.
courtesy AdrereAmellal.net
Palacio de Sal (Bolivia) —
At the Palacio de Sal, the walls, floors, beds and chairs are made entirely of white rock salt. An excellent stay if you're afraid of slugs.
Courtesy Palacio De Sal Hotel
1950s Bristol freighter plane (New Zealand) —
One of the last allied planes out of Vietnam has been converted into two self-contained motel rooms.
Courtesy Woodlypark.co.nz
Kadir's Tree Houses (Turkey) —
These simple wooden bungalows set amid the branches have long been popular with backpackers who like to party hard.
courtesy kadirtreehouse.com
Poseidon Undersea Resort (Fiji) —
Guests here are invited to interact with the surroundings -- at the push of a button the fish are fed, and the flip of a switch turns on sparkling underwater lights.
Courtesy Poseidonresorts.com
Kokopelli's Cave Bed & Breakfast (United States) —
Guests here stay in a carpeted, fully furnished room 21 meters below the surface, dug into a cliff face of 65 million-year-old sandstone.
Courtesy Kokopelli's Cave Bed & Breakfast
The Balancing Barn (UK) —
This precariously perched hotel was built by Living Architecture, the brainchild of Swiss philosophical writer Alain de Botton, who wrote "The Architecture of Happiness."
Courtesy Living Architecture
Hotel Saratoga (Cuba) —
The rooftop pool has some of the best views in town and goes some way to offsetting the traffic noise and hustle of the Paseo del Prado below.
Courtesy Flickr/ Col.Ho
Great Orme Lighthouse (UK) —
This old lighthouse has a 180-degree view over the cliffs of north Wales and the Irish Sea.