A religious shrine are the catacombs along the Appian Way, where drawings of the first Christians who used these rooms for prayer meetings and the burial of the dead have been preserved.
Just beyond the Aurelian Walls, a series of tombs along the Appian Way begins, the most famous of which is the tomb of Caecilia Metella. In 1302, Pope Boniface VIII gave this tomb to his Caetani relatives, who incorporated it into their fortified castle. At the end of the 16th century, the marble lining of the tomb was made.
The catacombs of San Callisto are still little explored. They are laid out on four levels and the tunnels are about 20 kilometres long. Some of the rooms are decorated with frescoes.
Above the catacombs of San Sebastiano rises the church of the same name. Numerous paintings on the walls of the refectory depict scenes of worship of the apostles Peter and Paul, whose remains were once hidden somewhere in these catacombs.
