This triumphal arch of Constantine is a centerpiece to historic Rome and celebrates the victory of Constantine. Made up of parts of earlier buildings, the arch is 21 meters high, 25.7 meters wide and 7.4 meters deep. The lower part of the monument is built of marble blocks, while the top (known as the attic) is composed of brick work and marble. A staircase as wide as the arch can be entered from a door near the bottom, in the end towards the Palatine Hill.