Originally commissioned by Marcus Agrippa, and subsequently rebuilt by Hadrian, the Pantheon is a monumental homage to the architectural finesse and ingenuity of the Romans. Massive bronze doors guard the entrance to the central space, sheltered by the graceful arch of the Pantheon's dome. The temple was transformed into a church in the early 7th Century by Pope Boniface IV and has remained well-preserved as a result. The building's primary source of light is the oculus, a circular opening at the dome's apex, rimmed with the original Roman bronze used at the time of its construction. Many famous Italians are buried in the Pantheon, including the Renaissance painter, Raphael, and King Vittorio Emanuele I.