26. Atomium
This fantastic building was built in Brussels for the 1958 World’s Fair. Standing 335ft tall, the structure lacks sufficient external support, so only six of the nine spheres are open to the public.
27. House Attack
While this traditional home wedged into the roof of Vienna’s modern art museum may look perfectly residential (except for being upside down), it’s an art piece designed by Erwin Werm.
28. Dancing House
Designed by Frank Gehry and supported by Vaclav Havel, this government administrative center in Prague looks like someone melted half an office building and smooshed it into the other half. It’s on the Czech 2,000-koruna coin.
29. Donut hotel
Recently built in Guangzhou, China, this enormous glowing donut is actually a hotel. It was designed so that the reflection of the building would form a number 8, a lucky number in Chinese culture.
30. Waldspirale
This German residential building complex looks like an organic layer cake and contains 105 apartments and a small courtyard with an artificial lake. It also has a green roof.