Procession in Catacomb of Callixtus. The Catacomb of Callixtus is one of the Catacombs of Rome on the Appian Way, most notable for containing the Crypt of the Popes, which once contained the tombs of several popes from the 2nd to 4th centuries.
   The Catacomb is believed to have been created by future Pope Callixtus I, then a deacon of Rome, under the direction of Pope Zephyrinus, enlarging pre-existing early Christian hypogea. Callixtus himself was entombed in the Catacomb of Calepodius on the Aurelian Way.
   The crypt fell into disuse and decay as the relics it contained were translated from the catacombs to the various churches of Rome; the final wave of translations from the crypt occurred under Pope Sergius II in the 9th century, primarily to San Silvestro in Capite, which unlike the Catacomb was within the Aurelian Walls. The Catacomb and Crypt were rediscovered in 1854 by the pioneering Italian archaeologist Giovanni Battista de Rossi.
   The catacomb forms part of an ancient funerary complex, the Complesso Callistiano, that occupies thirty hectares. The boundaries of this are taken as being the Via Appia Antica, the Via Ardeatina and the Vicolo delle Sette Chiese.
   The area of the catacomb proper is about fifteen hectares, and it goes down for five levels. A rough estimate puts the length of passageways at about twenty kilometres, and the occupancy at about half a million bodies. This catacomb's most ancient parts
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