It was built to commemorate the victory of Emperor Constantine over Maxentius in the Battle of Milvian Bridge in 312 AD. The Arch is based on an Opus quadratum with marble pylons. Numerous blocks were used for the precious sculptures that compose it and for the main structure.
With its twenty-one metres of height and twenty-six of width, it is the most important arch of the city, as well as the best preserved.
The Corinthian capitals and marble frames are considered amongst the finest ever made. They integrate perfectly with the central arches with simple profiles and deliberate imperfect geometry.
The monument has undergone several renovations over the years. The most complete one was in 1733, the year in which the integration work of the missing parts was done.