1. Masdar City, United Arab Emirates - Model city of the future
Masdar City is a planned community in the UAE that aims to be a sustainable city for technology and research. Still under construction, the city plans to incorporate hypermodern technologies such as personal rapid transit pods and wind gates to control wind flow and street temperature.
2. Setenil de las Bodegas, Spain - City covered in rocks
Setenil de las Bodegas is a small town with many of its buildings and residences built into the rock overhangs located in the region, providing a unique urban plan that conforms to the cliffs around it.
3. Petra, Jordan - Ancient city carved into stone
Although currently uninhabited, the city of Petra was first established around the 6th century BCE and eventually became an important post along trade routes connecting Asia and Europe. The entire city is carved into the red and pink cliffs of the region, including residences, government buildings, and places of worship.
4. Iquitos, Peru - Remote Amazonian masterpiece
Located in the middle of the Peruvian Amazon, Iquitos is part modern metropolis, part tropical jungle. It's the largest city in the world that cannot be accessed by road - you must fly in or take a boat if you want to visit.
5. Monsanto, Portugal - City of boulders
Located on a Portuguese mountaintop, the village of Monsanto contains houses built into the many large boulders and cliffs in the region.
6. Vardzia, Georgia - Medieval city of caves
Aside from a small group of monks maintaining the monasteries, the cave city of Vardzia is now largely abandoned. During its heyday in the Middle Ages, the city included a throne room, thousands of residences, and a complex irrigation system.
7. Alberobello, Italy - City of cones
Alberobello is known for its unique "trulli," dwellings constructed of limestone with distinctive conical roofs. The trulli construction technique dates back to prehistoric times.
8. Hallstatt Project; Huizhou, China - The charming European replica
This isn't exactly your typical European town. Instead, a Chinese real estate development company recreated the Austrian village of Hallstatt in the Chinese city of Huizhou, replicating the European architecture and layout in a completely different setting.
9. Göreme, Turkey - Where ancient rock dwellings meet modern life
Göreme is located in the Cappadocia region of Turkey, an area known for its multitude of unique rock formations. The valley around this region juxtaposes modern dwellings alongside traditional villages and towns carved into the side of the valley's rocks.
10. Seaside, Florida - City of immaculate proportions
Seaside is a master-planned community on the Florida panhandle renowned among architecture buffs for its precise proportions and design specifications. It's also well-known among film fanatics as the filming location for The Truman Show.
11. Songdo, South Korea - Pop-up city of technology
Having been built entirely since the new millennium began, Songdo is what many are calling an "instant city." The city intends to be extremely technologically forward, with underground pneumatic tubes to transport garbage and a "telepresence" video conferencing system connecting the entire city. Plus, it's going to include replicas of Central Park, Venetian Canals, and Parisian Boulevards to attract residents by the time the city is fully completed in 2015.
12. Coober Pedy, Australia - An underground civilization
The Australian mining town of Coober Pedy gets so hot in the summer that half of the town just decides to move underground to escape the temperatures. You can find hotels, restaurants, churches, and private residences all located underneath the Australian dirt.
13. Elista, Russia - The city that chess built
Elista is notable for its prevalence of Buddhist sculptures and temples as well as its emphasis on the game of chess. The city includes its own "Chess City" compound where various international chess tournaments take place. There are tentative plans to increase the scope of Chess City to include its own schools, museums, and religious centers.
14. Slab City, California - City of wanderlust and art
A former Marine camp, Slab City is now home to thousands of campers living in RVs and squatting in abandoned structures left over from the site's past identity. There's no government, electricity, or running water, but the town does have its own library and sculpture garden.
15. Thames Town; Shanghai, China - London style in the middle of China
Much like the Hallstatt Project, Thames Town is a planned community in China meant to mimic the architectural style of Europe - in this case, London.
16. Longyearbyen, Norway - City of beauty and isolation
Situated on the Norwegian archipelago of Svalbard in the middle of the Arctic, Longyearbyen is one of the most remote cities in the world. The city has a prohibition against burying bodies on the island because the cold temperatures prevent bodies from properly decomposing; anyone who dies in Longyearbyen must be transported to the mainland for his or her final resting place.
17. Auroville, India - City of communal harmony
Auroville is a community in Southern India centered on the principles of universality, peace, and progressive harmony. What's more, this city-in-the-making has actually received the backing of the Indian government as well as UNESCO.