Introduction During the ancient Rome, it was popular to cremate a person once he was dead. The ashes were preserved in urns and then stored in houses and sacred places. However, the Christians did not practice cremation since they believed in resurrection. Thus, they preferred to bury each other just like the early Christians did. Obviously, burying dead bodies required large areas of land (Athnos, 300). At the peak of the Roman Empire, the Christians did not own enough land to be burying their loved ones or even practice farming. So, the next option was to use catacombs. A catacomb is an underground area where the Christians used to bury their dead. Catacombs strengthened the Christians belief in resurrection and also acted as a place for displaying their art and symbols. Later, catacombs were also used by non-Christians to bury their dead too. It was initially thought that the Christians used the catacombs as hiding places. However, this assumption was dismissed since the catacombs were located near the highways. Also, the conditions inside them must have been unbearable due to the rotting bodies (Athnos, 367). The soft rock located in the area made it easy for the Christians to make tunnels or rather catacombs. The use of catacombs changed slightly when Christianity was made legal in the Roman Empire. It did remain as a burial place but also, it was a place of pilgrimage. A couple of centuries later after cathedrals were made; the catacombs were no longer used as a grave since most of the saints were buried in the church. They were now used as a memorial place for those Christians who were murdered because of their faith. By the beginning of the tenth century, the catacombs were no longer in use and eventually forgotten. This changed in 1578 after an unexpected finding by Antonio Bosio. Since then, there have been new discoveries of these catacombs; the recent one being discovered only decades ago. Around forty of these graves have been discovered since their first discovery in 1578. As far as Christian art is concerned, these catacombs are critically important since they contain a lot of different Christian art forms (Gough, 313). Description and History Among the biggest and well-known catacombs is the Catacomb of San Callisto. The catacomb occupies an area of nearly 15 ha with just over 500,000 graves and nearly 20 kilometres long. The catacomb of San Callisto was constructed at the beginning of 150 AD right under the modern Appian road. The catacomb is named after Saint Callixtus who was overseeing its expansion between 217 and 222 AD. It was further extended in the years between 366 and 384 under the then current pope; Pope Damasus. The expansion was a part of his attempt to boost the adoration of Roman martyrs. During this expansion, basilicas were built in the catacombs so as to make it easy for the worshipers to reach the martyrs’ graves. The San Callisto Catacomb has 4 levels with 5 parts; however, the 2 nd is the only one which tourists are allowed. All the rooms are connected to each other with channels. On the walls of the chambers, there are large holes which each were big enough to bury about 2 or 3 people. Figure 1 Other than that, there are cubicles large enough to bury several people. These cubicles