Located at the northern limits of the ancient city, the building is built in square blocks of limestone worked ashlar. It has two orders of arches, of which the lower order remains standing and some arches corresponding to the upper gallery. Remains of reticulated work are present in the corridors of vomitors. The cavea is divided into four wedges and the bands in which there were no steps probably received wooden stairs.
The orchestra floor, paved with limestone slabs allows the collection of rainwater in a large cistern under the pulpitum. The frons scaenae has two lateral quadrangular niches and a central, semicircular one. Remains of the architectural decoration are kept at the Civic Museum (Palazzo dei Consoli). In the same Museum there are also remains of an Augustean inscription that refers to restorations carried out by the city magistrate Cneo Satrio Rufo who "...at his own expense made the roof of the basilicas, fixed with iron the roof beams, made the stone floor...".