Rome, Italy - (4) Parthenon

The Pantheon is a building in Rome, Italy, commissioned by Marcus Agrippa during the reign of Augustus as a temple to all the gods of ancient Rome, and rebuilt by the emperor Hadrian about 126 AD. The building is circular with a portico of large granite Corinthian columns (eight in the first rank and two groups of four behind) under a pediment. A rectangular vestibule links the porch to the rotunda, which is under a coffered concrete dome, with a central opening (oculus) to the sky. Almost two thousand years after it was built, the Pantheon's dome is still the world's largest unreinforced concrete dome. (Source: Wikipedia)