The Catholic catacombs are very important for the art history of Early Christian art, as they contain the great majority of examples from before about 400 AD, in fresco and sculpture. The Jewish catacombs are similarly vital for the study of Jewish art at this period. The 1st sizeable catacombs were excavated from the second century onwards. Originally they were carved through soft rock outside the boundaries of the city, because Roman law forbade funeral places inside city boundaries. At first they were used both for funeral and the memorial services and parties of the anniversaries of Christian martyrs ( following similar Roman customs ). They were not used for regular worship. Many modern depictions of the burial grounds show them as hiding places for Christian populations during periods of persecution.

In 380, Christianity changed into a state religion. Initially plenty still desired to be buried in chambers alongside martyrs. Nonetheless the practice of catacomb funeral fell slowly, and the dead were increasingly buried in church cemeteries. In the 6th century burial grounds were used just for martyrs memorial services. Reputedly Ostrogoths, Vandals and Lombards that sacked Rome also violated the catacombs, doubtless attempting to find property. By the tenth century catacombs were practically abandoned, and holy relics were moved to above-ground basilicas. If you already know everything about Roma, another option is to take an appartement de luxe paris.
Now maintenance of the burial grounds is in the hands of the Papacy that has invested the Salesians of Don Bosco the supervision of the catacombs of St. Callixtus on the outskirts of Rome.
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