It was not a triumphal arch, nor was it dedicated to the figure of the famous Hispanic emperor. It was the monumental access gate to the sacred space (temenos) that surrounded a giant Imperial cult temple, the whole arch being surrounded by a portico. This temple, in turn, was surrounded by the provincial forum, where we know of the existence of another temple dedicated to the Augustan Concord, some of whose pieces are part of the Obelisk dedicated to the Martyr.

The rounded archway, which has a height of 15 meters, was the central opening of a gateway with three arches – the two side ones being smaller and segmental in nature. Its entire structure was done with granite ashlar masonry.

Today it is devoid of all the marble-plate cladding and inscriptions which it surely had. The trim is missing from the base of its vertical supports. Here, the axis that divided the city from south to north, the cardo maximus, ended. We can still see some stone slabs from said main street. Likewise, here the paving for the forum's public square began. As a curiosity, if you look to the floor, you can still see the hinges of the doors that closed this monumental door.