Under the Discount offers many early Christian catacombs, whose total area is about three square kilometers. Only some of them are open for visits.

The catacombs of St. Agatha are under the homonymous Church. Here is a pagan, Punic and Jewish burial, but the visitors only part of the Christian catacombs: the chamber tombs are the n sides of the dark and narrow corridors. On the walls of some tombs, the remains of ancient frescoes.

Catacombs of St. Paul are also a maze of narrow corridors carved in stone chambers-grobnica along the walls.