An Igloo: There is no more sublime experience than being suffused by the Northern Lights. To do so in a glass igloo must surely be one of the more novel and cosy ways of admiring one of nature’s most stunning phenomena.
Situated 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 and utterly chic, but somewhat lacking in privacy.
A Sewer Pipe: Stay overnight in a concrete sewer pipe on the banks of the River Danube.
The drainpipes are two meters in diameter and two and a half meters long, with a porthole to look out of, a front door to close and a cozy nest to snuggle into, which includes a low-slung futon, bedside lamp, woolly blanket and light sleeping bag.
A Fishbowl: Originally a research laboratory, the world’s only underwater hotel sits at the bottom of the Emerald Lagoon in Florida’s Key Largo, and can only be reached by scuba diving down six meters. The real attraction are the fish; the lodge is like a goldfish bowl in reverse, where you sit and watch angelfish, parrotfish, barracuda and snappers peering in at you through the window.
A Cave: One of the oldest cave hotels in the area, Kismet Cave House has built a loyal following of repeat guests who return for the hospitality as well as the unique, affordable lodging. It's an intimate hotel with just eight rooms operating like a bed and breakfast -- slim on facilities but big on personality with simple but delicious food and distinctive furnished rooms that show off the owner's collection of Turkish rugs.
A Yurt: Boutique Camping is a three-pearl bespoke "glamping" (glamorous camping) site set on a 100-acre organic sheep farm. There is an assortment of 26 different accommodations available, from traditional Mongolian Yurts to a range of boutique guest houses, huts, and free-standing caravans. Guests have shared access to the converted loft space, with a fully-equipped kitchen, large communal dining tables, fitness facilities, and a sauna.
A Monastery: The 45-room Hotel San Francesco al Monte is a charming property converted from a 16th-century monastery. The highlights here are panoramic views over the city rooftops to the Bay of Naples -- from the seasonal outdoor pool, pleasant roof garden, and many of the rooms. Rooms have frescoes and gilded headboards that remind guests of the property's origins.
An Ice Room: The hotel remains between 23 and 27 degrees Fahrenheit at all times, and overnight guests are given thermal sleeping bags for extra warmth.There are lockers and public bathrooms with stall showers, as well as a small cafe, three bars serving beer and cocktails in glasses made of ice, and an outdoor spa with hot tubs and saunas, which guests can use throughout the night.
A Jail Cell: This 95-room, upscale boutique hotel is housed in a beautifully refurbished former Victorian prison that retains a large portion of its original fixtures. t's hard to imagine that the posh surroundings once housed (and hanged) British prisoners, though period furniture and preserved dungeon-like punishment cells are scattered throughout the property.