The term “catacombs” refers to subterranean burial grounds. They can be found almost anywhere; however, the most famous catacombs are located in Rome.
They date back to the early Church. Most of the catacombs of Rome are technically located outside the walls of the city on Via Appia Antica, a major road that leads from Rome to the south of Italy. Burial grounds for Christians are an important theological point.
First, pagan Romans didn’t believe in the afterlife like Christians did. Therefore, when pagans died, they would be cremated, and their remains could be used as amulets, or scattered wherever they wished. Christians definitely believe in the afterlife. The whole idea of suffering and persevering in this Valley of Tears called Earth is possible, because Jesus rose and ascended and prepares a place for us.
In vast contrast to pagans, Christians have great respect for the body. The body, by Baptism, is a temple of the Holy Spirit and therefore even in death the body must be treated with respect.
Second, Christians believe in the resurrection of the body. So the earthly remains are buried in anticipation that at the end of the world the body will rise from the dead and be reunited with the soul. Burial grounds became important places for Christians. During the Roman persecution, catacombs were used because they were not in the sight of the enemy. There are many tunnels, and a person could easily escape the threatening hand of the law. Catacombs also became early worship sites. On tombs of martyrs or saints, the Holy Sacrifice of the Mass would often be celebrated. This was done out of respect for the sainted person and also to be close to the saint in order to obtain the same graces of perseverance.
Of the many catacombs in Rome only five are open for tours, and only certain tunnels are open to the public. Most of the tunnels were pillaged and are now empty because of the Barbarian invasions during the fifth century, when the pillagers looked for money and valuables.
On the Via Appia, one can visit the catacombs of Domitilla, Saint Sebastian, Callistus, and Saint Agnes. Priscilla is located in the north of Rome and was a part of Villa owned by Priscilla, a wealthy convert to Catholicism. The art of the catacombs is the earliest form of Christian art; the catacomb of Priscilla contains the earliest artistic rendering of Christ. He is pictured as a shepherd carrying a sheep over his back.
Catacombs also display many Christian symbols used so that the pagans could not understand—symbols like the Chyro, Alpha and Omega, and dove with a fern.