All the typologies of arches, vaults and domes come from the operations stated in the previous section. They are comprehensively collected and explained in each correspondant Wikipedia article. Curved shapes were used in the past for covering large rooms in buildings, as happened for example in the Domus Aurea of Emperor Nero, the Basilica of Maxentius, the Pantheon, Rome, or Hagia Sophia. However, they could be used for infrastructures too. For instance, the Ancient Roman civilization exploited curved structures for bridges, aqueducts, sewage ducts, and arch-dam. The main materials of such constructions were Masonry and Roman concrete.