The Catacomb(s) 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.
The underground cemetery includes several areas. The area of the Popes is the most important and venerated crypt of the cemetery, called 'the little Vatican' as it was the official burial place of nine popes and, probably, of eight dignitaries of Rome's 3rd century Church. In the walls you can still see the original inscriptions, in Greek, of five popes. On four tombstones, near the name of the pope, there is the title of 'bishop', since the Pope was regarded as the head of the Church of Rome, and on two of them there is the Greek abbreviation of MPT for 'Martyr'.
Passing through imposing galleries full of loculi, we reach five small chambers, truly family tombs, commonly known as the cubicles of the Sacraments, and particularly important for their frescoes.References:
The eight towns in south-eastern Sicily, including Ragusa, were all rebuilt after 1693 on or beside towns existing at the time of the earthquake which took place in that year. They represent a considerable collective undertaking, successfully carried out at a high level of architectural and artistic achievement. Keeping within the late Baroque style of the day, they also depict distinctive innovations in town planning and urban building. Together with seven other cities in the Val di Noto, it is part of a UNESCO World Heritage Site.
In 1693 Ragusa was devastated by a huge earthquake, which killed some 5,000 inhabitants. Following this catastrophe the city was largely rebuilt, and many Baroque buildings from this time remain in the city. Most of the population moved to a new settlement in the former district of Patro, calling this new municipality 'Ragusa Superiore' (Upper Ragusa) and the ancient city 'Ragusa Inferiore' (Lower Ragusa). The two cities remained separated until 1926, when they were fused together to become a provincial capital in 1927.