Inspired by the symbolism of the circle and the sphere, architects have been designing circular buildings since the ancient times. Round towers and spherical domes have been used notably throughout the Greek and Roman times, and more recently in modern architecture in the development of planetariums and theaters. Nearly all of these buildings use the circular shape in the floor plan, but in these five examples the shape has been utilized in the vertical orientation.

Al Dar Headquarters, Abu Dhabi

The Al Dar Headquarters, located in Abu Dhabi, looks like a coin standing on its edge. It comprises of two circular convex shaped facades linked by a narrow band of indented glazing. This iconic fully glazed structure is completely circular in elevation and curved in all other directions. The building is 121 meters tall and has 23 floors. The building was designed by MZ Architects.

Sunrise Kempinski Hotel, Beijing

The Sunrise Kempinski Hotel, about 60 kilometers from Beijing's city center, is said to look like the rising sun, while from the side, the hotel takes on the appearance of a scallop, which represents fortune in Chinese culture. Opened in November last year, the eye-catching 97-meter-high luxury hotel sits on the shore of Yanqi Lake and has 21 floors filled with 306 guestrooms and suites, along with meeting rooms, recreational and fitness facilities and a range of restaurants and bars. The building was designed by Shanghai Huadu Architect Design Co.

Guangzhou Circle, Guangzhou

The doughnut-shaped Guangzhou Circle is located in the Chinese city of Guangzhou. It is the current headquarters of the Hongda Xingye Group and the new home of Guangdong Plastic Exchange, the world largest trading center for raw plastic material. Located on the edge of the Pearl River, the 138-meter Guangzhou Circle was designed by Di Pasquale of Milan studio AM Project. A circle with a 50-meter diameter punctures the heart of the 33-story structure, turning the building into a hollow circle. When reflected in the river, this shape becomes a figure of eight - a lucky number in Chinese culture.

Fangyuan Mansion, Shengyang

Fangyuan Mansion in Shenyang, also in China, rises 100 meters and was designed to look like an ancient Chinese coin. Completed in 2011, Fangyuan Mansion was designed by C.Y. Lee & Partners Architects/Planners, who had also designed the famous 508-metre Taipei 101 skyscraper, currently the third-tallest building in the world.

Fangyuan Mansion was once voted one of the world’s ugliest building by CNN.

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Radisson BLU Hotel in Frankfurt

The Radisson BLU Hotel in Frankfurt is a concrete structure competed way back in 2005. Designed by architect John Seiffert, the disc structure is made of glass and features cubes of structure between the front and rear facades.

Photo credit: Radisson BLU

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