The catacombs of Sant'Antioco are located next to the Basilica of the Saint and extend south east of it, in underground environments derived from the Punic necropolis. Inside there are arcosolium tombs and a sarcophagus (E environment) which still have the remains of the frescoes with which they were decorated. The small catacomb in Is Pirixeddus also contains a painted arcosolium. The themes of the frescoes derive from early Christian symbology: the figure of the Good Shepherd (fig. 1), the ribbon patterns and floral motifs up to the depiction of a robin; they are symbols which represent the resurrection and Paradise.

Fig. 1 - Typical depiction of the Good Shepherd in the catacombs of Priscilla in Rome (from http://it.wikipedia.org/wiki/Catacombe_di_Priscilla#mediaviewer/File:Good_shepherd_01_small.jpg).

The graves could also contain inscriptions, as in the case of arcosolium C / VIII, the only one of the whole catacomb, in capital letters: EVIBAS (...in pac]e vibas [...). (figs. 2-3).

Fig. 2 - Arcosolium C / VIII, the remains of the frescoes, view from the right side (from PORRU 1989 table XVa).

Fig. 3 - Arcosolium C / VIII, the remains of the frescoes. View from the left side (from PORRU 1989 table XV b).

The other decorations have mostly geometric or floral patterns (figs. 4-5).

Fig. 4 - Reconstruction drawing of the exterior decoration of arcosolium L/XXI, arch and front (from PORRU 1989, table XVI a)

Fig. 5 - Reconstruction drawing of the exterior decoration of arcosolium L/XXI, section and enlarged view of the floral decoration (from PORRU 1989, table XVII a)

The last arcosolium painting was found in the necropolis of Is Pirixeddus. What may now be observed on site is a reproduction of the original fresco which contains the idealised portrait of the deceased man or woman (unclear), under a sort of canopy, flanked by baskets filled with pomegranates, a symbolic fruit in Christian iconography, connected to the resurrection. dimensions (fig. 6).

Fig. 6 - Reconstruction of the arcosolium found in Is Pirixeddus (from Bartoloni 2007, p. 50, fig. 31).

Another fresco, this time relating to a sarcophagus, is located inside chamber E. This is a geometric decoration divided into squares defined by strips of alternating colours (green, yellow, red). Only a head is readable, while traces of the same motifs remain along the long side. The cover was also painted (fig. 7).

Fig. 7 - Painted sarcophagus in E chamber, view of the entire head (from PORRU 1989, table XXII c)