St. Stephen's Cathedral is the "mother church of the Roman Catholic Archdiocese" and is considered the most important religious building in Vienna. The current Romanesque and Gothic form of the cathedral stands on the ruins of two earlier churches and the roof is made up of 230,000 multi-colored and ornately patterned tiles.
The Hendee-Borg House is a symmetrical saw-tooth roof house, which is made up of ridges with dual pitches in order to admit natural light into the building.
The Upside Down House, as it is called, is located in Szymbark, Poland and is symbolic of the effects of communism in this country: quite literally it has turned this home upside down.
The Tongkonan is a traditional house of the Toraja, an indigenous people on the island of Sulawesi in Indonesia. Tongkonan, which means "to sit," are usually built facing north-south and the most notable thing about these houses are the roofs.
Residence Alma, a 1960s pitched-roof house in the Dolomites (a mountain range in Italy) is a beautiful and unique combo of traditional and modern that makes a great conversation starter.
Although it looks like an airplane that missed the landing strip, this is actually a two-story "airplane house" (Airbus A380 house, to be exact) in Miziara, Lebanon.
The Beijing National Stadium, a.k.a. "the bird's nest" due to the "web of twisting steel sections that form the roof," is the world's largest enclosed space and largest steel structure.
La Pedrera ("stone quarry") is the more popular name for Casa Milà, designed by architect Antoni Gaudí, who created a roof with sentinels to stand guard, and took six years to build (1906-1912). In 1984, it was declared a World Heritage building by UNESCO. You can even take a tour of this spectacular building!
The Qizhong Forest Sports City Arena in Shanghai is an 8-piece roof that takes eight minutes to fully open or close, which means that it can be used for either indoor or outdoor tennis events.
The Hotel Marques de Riscal in Spain might look like a ball of tangled ribbon, but it is actually the work of renowned postmodernist architect Frank Gehry, who also designed the Walt Disney Concert Hall in Los Angeles and the Guggenheim Museum in Bilbao.