Tiddis, located about 30km from Constantine, offers a striking location for a Roman site perched on a barren mountain slope. Originally settled by Neolithic Berbers, the Romans developed it into a fortress, Castellum Tidditanorum, during the reign of Augustus. The town's unique layout features two central streets, typical of Roman town planning, adapted to the site's topography. Key highlights include the cisterns and channels used to collect rainwater, circular tombs (some pre-Roman), a Roman arch at the entrance, and remains of homes, sanctuaries, olive presses, and baths. The Villa of Mosaics showcases mosaics and other remnants. The site requires private transport from Constantine for access.