This monument, dated back to the fourth century AD, is located near the Church of San Giorgio al Velabro and the Arch of the Argentari (Silversmiths). The arch, erroneously known as the arch of Janus, is identified as the ancient Arch of the Constantines.This is a four-faced arch (with four passages) that consists of four pillars with niches on their external faces holding statues. Minerva and Ceres standingand Rome and Juno seated are depicted at the center of the external arcades. Fragments of a not very legible inscription coming from the top of the arch were transferred to the Church of San Giorgio al Velabro during the Middle Ages: they indicate that the arch was probably dedicated to the emperors Constantine or Constant the Second.