The Altar of Peace, also known by its ancient name, Ara Pacis, is a 1st century BC monument embellished with marble reliefs. The structure's carved stone surfaces depict religious processions and allegories, all of which glorify the family and virtues of the Emperor Augustus. Inaugurated in 9BC, the altar was a destination for ritual and sacrifice for four centuries, after which time it was neglected and ultimately buried by deposit left by Tiber floods. Its rediscovery took centuries and culminated in a Fascist-era excavation, followed by the repositioning of the monument in its current location beside the Tiber River. In 2006, American architect Richard Meier completed the Museo dell'Ara Pacis, the glass and limestone building that houses the Altar, as well as numerous exhibition spaces.