Roma Porta S. Paolo

Sitting adjacent to the ancient Pyramid of Cestius and the ruins of the Aurelian Walls, Porta San Paolo marks one of ancient Rome's southern gates, though today the site is best known practically as the departure station for the Roma-Lido train line to the beach town of Ostia. It's a lower-key, functional stop compared to the grander landmarks nearby, more of a transit hub than a destination in its own right. Travelers pass through mostly on their way to or from the coast rather than to admire the gate itself. It's worth a glance if you're already in the area for the Pyramid or Protestant Cemetery.