Anyone who's been to Spain in the last few years can attest to the outpouring of creative energy there. (The dramatic new Terminal 4 at Madrid's Barajas Airport is just one example.) The buzz peaks at this 342-room hotel that's 20 minutes by car from downtown Madrid. Nineteen architectural and design firms representing 13 nationalities were involved in the construction and each of the 12 guestroom floors; each bears the imprint of a single cutting-edge designer. Norman Foster did the second floor, Seville-based Victorio & Lucchino did the fifth; and Jean Nouvel, the twelfth. The ground floor's Marmo Bar features a single, 27-foot-long slab of marble, while the top floor has a pool, gym, sauna and the Sky Night bar (also designed by Nouvel). To get a flavor for the different styles, guests are encouraged to change floors every night.

For more information: Hotel Puerta America

Though it sits squarely on Playa del Carmen, the Básico is not your ordinary beach hotel. Architect Moises Ison created a completely concrete structure the walls of which define not just the exterior but inner guestroom walls as well. There's also a uniquely Mexican spin on recycled materials: the lobby floor is made from old tires, rocking chairs are made from rubber and two oil tanks were repurposed as miniature swimming pools and plunked down side by side on the roof. Rooms get plenty of natural light and oversized planters with iridescent tiles add a tropical touch to the somewhat severe surfaces. Look for fins and a soccer ball under the bed: subtle but practical reminders that you're a long way from the constraints of urban hip.

For more information: Hotel Básico

Leave it to perpetually hot hotelier Ian Schrager to create a hotel that is the aesthetic opposite of the minimalism he pioneered with the Royalton and Morgans in the '80s. His unique collaboration with artist Julian Schnabel has brought "rock with a Baroque twist" to the formerly staid Gramercy Park Hotel. Now, it's steeped in a palette of Renaissance colors and fairly bursts with unexpected and eccentric stylistic collisions that are so bold they nearly clash. Madonna recently threw a party in the lushly landscaped private Roof Club.

For more information: Gramercy Park Hotel

Heading north on the road that leads to the Baths of Aphrodite, one could be forgiven for mistaking the five-star resort Anassa (Greek for "queen") for a postcard-perfect whitewashed Greek island village. That's what it most closely resembles, right down to the Greek Orthdox-style chapel. But once inside, the Mediterranean meets the 21st century with breezy common areas thoughtfully peppered with Cypriot antique furniture. One of the restaurants, Basiliko, has a vaulted ceiling that evokes the Byzantine churches of Cyrus. From Anassa's private beach, there are sweeping views of the Akamas Peninsula, one of the last unspoiled landscapes in the Mediterranean and the spot where Aphrodite is said to have frolicked with Adonis. Four-by-four jeep excursions can be booked through the concierge.

For more information: Anassa

If you're going to the Great Wall of China, you may as well stay in a great hotel. This one-of-a-kind, Chinese-owned and German-managed hotel—situated by the wall's Shuiguan section—didn't start out as a hotel. Rather, it was a collection of modern houses designed by a dozen leading Asian architects. Today, the property consists of 31 villas divided into about 100 rooms and suites, as well as the original 11 homes which are now presidental suites. The cool if spartan design would not be out of place in an oasis of mid-century modern architecture like Palm Springs, making it all the more striking to see in this verdant, far-flung setting. Stark geometric shapes leave plenty of room for wide windows—indeed, many of the walls are made entirely of glass, quite a contrast to the famous fortification that looms nearby.

For more information: Commune by the Great Wall Kempinski

In a city that practically invented surrealism, a hotel within a hotel might not come as a surprise. The outwardly staid Royal Windsor, barely a five-minute walk from Brussels' Grand Place, counts a dozen rooms among its total of 266 that were designed from top to bottom by Belgium's most talented designers. Each was created as though the room were the designer's very own. The Nicolas Woit room has a pink velvet daybed, pinpoint lights above the actual bed and velvet frosted mauve curtains.

For more information: Royal Windsor Hotel

In a city where feisty and fiery emperors once held sway, a luxurious heaven-and-hell-themed hotel seems almost like a prerequisite. Aleph, designed by Adam Tihany, in a space that used to be a bank, fits the bill. Beyond the Japanese warrior costumes at the entrance, the lobby is a riot of red, with plush fabrics and mod furnishings creating the louche feel of a neo-Roman bordello. When you're done sinning in the room, descend to the heavenly angel-white spa and pool area in the hotel's underground. (Sure it sounds upside-down, but when in Rome…) Each guest room is outfitted with a wall-sized black-and-white photo of a Roman monument or street scene. The Do Not Disturb signs are made of brightly colored, squishy orbs.

For more information: Aleph Hotel

One of French superstar architect Jean Nouvel's earlier major commissions was a curiously modern hotel in an unexpected locale: the wine village of Bouliac, outside Bordeaux. And it's an affair as high-tech as Bordeaux's wines are classic. The façade is laced over with grills of core-ten steel, reminiscent of the metal used by local farmers to barricade livestock. Only, these ones were actually designed to rust over. Thanks to innovative hydraulics guests can adjust the grills from inside using a bedside remote control. The colors of Nouvel's signature window grids change with the fluctuating daylight from orange to red, copper and black. The corridors feature rotating contemporary art installations.

Rising like a 21-story glass beacon over the Lower East Side's sea of red brick tenements, the Hotel on Rivington opened in late 2004 and serves up heaping portions of rare Manhattan commodities like light, air, and space. In fact, the clear glass walls would be striking in any setting, but here they do no less than shock. Zen-sleek bathrooms feature glass shower walls—a "conceal and reveal" component that enables you to take in the cityscape while preserving privacy. On the ground floor, the hotel restaurant Thor is always abuzz with an assortment of global hipsters, who dine under a soaring glass ceiling that affords starkly dramatic views of historic six-story tenements.

For more information: Hotel on Rivington

Extreme design hotels aren't always located in cities. Michel Bras, in the middle of France's Aubrac region, is a clear example. The sight of this unabashedly contemporary hotel and restaurant rising from the rocky meadows in what could be considered France's little Wyoming, is nothing less than jarring—but in an uplifting and somehow very French way. Oversized windows predominate, throughout, and guestrooms bask in natural light. The low-slung rectangular shape of the freestanding bedroom pavilions echoes that of farming huts in the region, and all the granite used was sourced locally. In the gourmet restaurant, flavors are crisp and draw heavily on local vegetables. The bovine shape of the chair legs are subtle nods to Aubrac dairy cows.

For more information: Michel Bras