Like planners, venue operators have been coming up with unexpected themes as a way to entice—and immerse—guests. In fact, a number of places take their design concepts to the extreme, and in some cases have even influenced events. In one instance, a Swedish hotel made almost entirely from snow and ice inspired designer Karl Lagerfeld to build an iceberg as the centerpiece for the 2010 Chanel Paris Fashion Week show.
For those looking for new ideas—or are just plain curious—here's a roundup of some of the most unusual themed venues from around the world.

In the Swedish village of Jukkasjärvi is the IceHotel, a space built every winter from a combination of ice and snow. Snow is sprayed on huge steel forms; once the snow is frozen, the forms are removed, leaving free-standing corridors of snow in which dividing walls are built to create rooms and suites. Hotel guests sleep in thermal bags, and the site also offers an ice bar and church.

Noah's Ark, an amusement park, restaurant, and event center, opened in July in Dordrecht, a city in the western region of the Netherlands. The venue was built to the dimensions of the biblical vessel and includes life-size animal sculptures, two amphitheaters, and a restaurant.

Built in the shape of a beagle, the Dog Bark Park Inn is a bed-and-breakfast in Idaho owned by husband-and-wife team Dennis Sullivan and Frances Conklin. The canine-inspired accommodations, which sit inside a 30-foot-tall structure dubbed Sweet Willy, is big enough for four guests—plus their four-legged companions.

Jutting out from the jungle canopy of Costa Rica is a hotel suite built inside the fuselage of a 1965 Boeing 727 plane. Part of the Hotel Costa Verde, the two-bedroom, teak-paneled space has a cockpit as well as balconies on each wing and offers views of the neighboring Manuel Antonio National Park.

The Yellow Submarine hotel, a narrow boat renovated by businessman Alfie Bubbles, opened in Liverpool last year. The unusual tribute to the Beatles, the band's popular song, and the 1960s, is designed to look like a submarine on the outside and features psychedelic decor and furnishings inside. According to The Daily Mail, the three hotel rooms available on the boat come with 3-D TVs and Wi-Fi.

San Francisco tourist spot Alcatraz is apparently popular enough to spawn imitators. Based on the infamous island prison and perhaps the wackiest themed restaurant in Tokyo, Alcatraz E.R. offers a prison hospital theme, with jail cells, waitstaff dressed as nurses, and a menu of bizarre dishes designed to look like body parts.

CasaBubble, which rents transparent spheres for events, also works with hotels like Le Cottages du Parc in France. Envisioned by French designers Frédéric Richard and Pierre-Stéphane Dumas, the pressurized bubbles are designed to be used as lodging in outdoor environments and can include additional sections to house a bathroom or dining area.

The world's first Barbie-themed restaurant—at least, the first officially licensed by the iconic doll's parent company, Mattel—opened this year in Taiwan. Although the brand has created experiential versions of Barbie's Dreamhouse and Closet at events, Barbie Café in Taipei's shopping district is a permanent fixture, with tutu-inspired chairs, tables in the shape of stilettos, a color scheme of pink, and a full menu.

Lego is the theme of a 250-room hotel scheduled to open in April in Carlsbad, California. The venue, the first Legoland Hotel in the U.S., is geared toward families and evokes the brightly colored building blocks through decor and models. In the bedrooms are murals, furnishings, and fixtures designed after Lego's kingdom, pirate, and adventure collections.

Horror films and dungeons appear to be the main inspiration behind the prison-themed Lockup restaurant chain in Japan. Designed like a haunted house, the izakaya-style eatery comes complete with skeletons, mask-wearing staffers, and drinks in test tubes.

Getting to Kokopelli's Cave Bed and Breakfast requires a bit of a hike. Uniquely positioned in a man-made cave north of Farmington, New Mexico, the one-bedroom inn has its entrance in a cliff face, which is accessed via a short ladder. Inside, Southwestern-style furniture and decor contrast with the rough walls.

For animal lovers, Toyko is home to several bunny cafés, coffee shop-pet store hybrids that let patrons play with and feed the furry creatures. Usagi Cafe Ohisama, also known as Rabbit Sun Café, has bunny-themed decor and a separate play room for its 20 or so in-house rabbits.

Part of a movie set built in the 1940s for western films, Pappy & Harriett's Pioneertown Palace is an Old West-themed tavern and music venue in Joshua Tree. Inside, there's exposed brick, live music, and a menu of items barbecued on an outdoor, mesquite-burning grill.