The catacomb is actually three separate burial chambers that were joined to create a single network. They were opened in the early 3rd century, and were named after the deacon Callixtus, to whom Pope Zephyrinus (199-217) gave the responsibility for the catacombs.
It was rediscovered by the archaeologist Giovanni Battista de Rossi (1822-1984) in the 19th century. At a gardener's cottage, probably identical with one of the chapels on the surface, he discovered that one of the steps in a stone staircase has an inscription: ...NELIUS MART. Knowing that the martyr Pope St Cornelius had been interred in the catacomb of St Callixtus, he searched the area and found an entrance. There, he stumbled across a part of the same insciption, saying COR.... Excavations started in 1849, and soon after, de Rossi brought Pope Pius IX to the Chapel of the Popes. The Holy Father was so moved by his visit to the burial place of so many of his saintly predecessors that he fell to his knees and wept.
Chapel of the PopesEdit
This chapel is one of the first rooms after the entrance. In the 3rd century, nine popes were interred here. Among them was Pope St Sixtus II, who was martyred here in 258. He was followed here, and while reading Mass he was apprehended and executed together with several Deacons.
The inscribed slab on the tomb of Pope St Cornelius (251-252) was placed here by Pope St Damasus I (366-384). During excavations, fragments of it was found, and the missing pieces have been reconstructed from manuscripts quoting the verse. The Byzantine paintings depict Pope St Cornelius and his close friend St Cyprian of Carthage.
The following crypts form part of the chapel.
Crypts of LucinaEdit
Named after the Roman matron who originally owned the catacombs and allowed Christians to bury their dead here, these crypts contain early paintings.
Crypt of St CeciliaEdit
St Cecilia was originally interred here. In 821, Pope Paschal I collected the mortal remains of martyrs and early Christians from the catacombs to protect them from raiders. He searched for her relics, but they could not be found. But in a dream, he was told where they were, and subsequently discovered her incorrupt body in this chapel. They were then moved to Santa Cecilia in Trastevere.
Crypt of St EusebiusEdit
Named after Pope St Eusebius (309), this crypt has an inscription by Pope St Cornelius that is of interest to Church historians. It mentions the question of the lapsi, those who has denied their faith rather than die as martyrs. At Cornelius' time, one of the important debates in the Church was how they should be treated if they wished to return to the Church. Pope St Caius (283-296) was buried here, as were the martyrs Sts Calocerus and Parthenius, who probably died in the persecution of Diocletian.
Cubicula of the SacramentsEdit
On the walls of this room are paintings of Baptism and the Eucharistic Meal. They are from the early 3rd century, and are among the earliest known Christian paintings.
Crypt of MiltiadesEdit
The crypt was dug in the 4th century, and dedicated to Pope St Miltiades (also known as Melchiades).
Chapels on the surfaceEdit
The two chapels were originally tricora, mausolea from the 3rd century.
In the eastern one, a multiple burial was found in the floor It contains the bodies of, among others, Pope Zephyrinus and St Tarsicius.
The western one was probably the gardener's house where the de Rossi found a fragment from the tomb of Pope St Cornelius. It is filled with fragments of sarcophagi found in the area. In 1994, de Rossi's tomb was transferred here in honour of his great discovery.