The Ara Pacis Augustae (Latin, "Altar of Augustan Peace"; commonly shortened to Ara Pacis) is an altar in Rome dedicated to Pax, the Roman goddess of Peace. The monument was commissioned by the Roman Senate on July 4, 13 BC to honor the return of Augustus to Rome after three years in Hispania and Gaul, and consecrated on January 30, 9 BC. The altar reflects the Augustan vision of Roman civil religion. It consists of a traditional open-air altar at its center surrounded by precinct walls which are pierced on the eastern and western ends by openings. The Ara Pacis is perhaps best known for the decoration on the exterior of the precinct walls composed of two tiers of friezes. On the north and south, the upper register depicts the procession of members of the Imperial household and the larger regime, while on the east and west, panels depict allegorical themes of peace and Roman civic ritual. The lower register of the frieze depicts vegetal work meant to communicate the abundance and prosperity of the Roman Peace (Latin: Pax Augusta).