The merlionated gate, with Baroque decoration is located on at exit point of Via Garibaldi, where it meets highway SS2 as it skirts the historic center of Viterbo, region of Lazio, Italy.
South of the gate is a train station (Stazione di Viterbo Porta Romana), with local lines linking to Rome, and just west is the campus of Tuscia University, which occupies some of an old Dominican monastery and Villa Gentili.
It replaced the Porta San Sisto, which is now incorporated into a tall tower to the right of the door, that serves as a bell-tower for the church.
Facing outward, above the portal is a depiction of the youthful Santa Rosa of Viterbo, patron saint of the town.
The gate at the time was named Porta Pamphilia, or Innocenziana, because it was inaugurated in 1643 when Pope Innocent X Pamphili came to visit his sister-in-law Olimpia Maidalchini.