Porta Gemina or Romana owes its name to its location, on the side of the town facing towards Rome. It represents Ascoli’s most interesting defensive system: in fact, the town is naturally protected by the two rivers surrounding its city center and this side was the only one lacking of protection. Today’s Porta Gemina is composed by two round arches resting on three travertine pillars. Inside the arches, it is still possible to see the tracks where the shutters used to roll up and down.