Catacombs were stone-walled underground cemeteries, usually for one or more wealthy Roman families. In that sense, Saint Priscilla's catacombs on the Via Salaria, are really no different than many others in the city of Rome. However, painted on the walls of these catacombs are numerous frescos dated to the 2nd and 3rd centuries AD.On the ceiling of a niche dug out from the upper wall of a gallery is the Good Shepherd, a symbol of Christ amid trees with stucco trunks with painted branches bearing red and green flowers.
Also, an image of the Madonna and Child with a prophet pointing to a star."A star shall come forth out of Jacob, and a sceptre shall rise out of Israel."
The style of the fresco and its location contribute in dating the image to the beginning of the third century A.D. making it the oldest known image of the Mother of God. 
