It's one of the huge arches ever built in Rome. Its height reaches 21 meters, almost 36 meters of its width, and the thickness of its walls is superior to 7 meters. Arch was built in 315 by decree of the Senate and people of Rome to celebrate the tenth anniversary of the reign of Constantine, and the victory won by them in 312 at the Battle of Ponte Milvio against Maxentius. For the decoration of the arches used a lot of bas reliefs and sculptures taken from other sites. Both large arch abutments are four columns, dating back to the reign of Trajan; columns towering over the eight statues of Dacian white with purple-veined marble of Asia Minor.

Above the side arches are eight medallions era of Hadrian, grouped by two above each arch. Four images they reproduce scenes of hunting scenes, four others - sacrifice. On both sides of the line, repeated in two tapes attic, you can see eight reliefs era of Marcus Aurelius, adorned once another triumphal arch and also placed two on each side. The bas-reliefs depict the solemn moment of "Return of the Emperor" in 173, after the victorious battles with the Germanic tribes of Marcomanni and quads. Large marble frieze Trajan's era is also borrowing. It is divided into four parts: two pieces are placed on small arches, and two - in the central span. Sculptural reliefs reproduce scenes of Trajan's military campaigns against the Dacians (101-102 and 105-106 years).