The surviving single arch is of
travertine, 8.80 metres high, 7.30 wide, and 3.50 deep. It is supported by piers which are 1.40 metres wide and 3.50 deep. Outside these piers, there are two
pilasters of the same depth, topped by
Corinthian capitals. The pillars support a horizontal
entablature which is 2 metres high and contains a dedicatory inscription on the
architrave. There is a simple
cornice on each side of the arch, beneath its spring. A drawing of the 15th century shows small side arches. These pedestrian arches were demolished during the 15th century. ==Inscription==