Tunisia - Jebel Oust

Archaeological research at Jebel Oust

The ancient site of “Jebel Oust” is located in Hammam el Oust (32 kilometres south of Tunis, on the road to Zaghouan). The ancient name and nature of the site (city or place of worship surrounded by several settlements?) are unknown. It could be the site of Onellana, which appears in the Tabula Peutingeriana, equidistant from Oudna and Thuburbo Maius, but this is not certain. The site, which was first identified in 1862, was not excavated until 1907, following the (re)discovery of the groundwater table at 55° by a mine prospector. The circular pond and the large rectangular pool, the columns of which emerged from the ground, were hastily excavated by the military. The site was then forgotten about until around 1955, when Mohammed Fendri uncovered the three elements that are now visible: the thermal baths, the temple quarter and the cisterns. A few preliminary papers were published on the site, but it remained, for the most part, untouched. The purpose of the Jebel Oust archaeological expedition led by Aïcha Ben Abed and John Scheid is to restore and study the monuments uncovered in 1962/3 and subsequently publish the findings.

Located on the side of a hill facing east, the site consists of two main zones: the structures built around the source of a warm spring, and a group of three cisterns that run alongside the holy site to the south. These cisterns, which diverted only a small proportion of their potable water to the ancient site, were probably meant to serve as a secondary water source and a reserve for the Carthage aqueduct, 2km north of the site.

The site developed out of a natural phenomenon: the warm spring that flowed down the slopes of Jebel Oust. A place of worship was built around the source. During the first identifiable phase of the site’s occupation, this consisted solely of a court with two rectangular exedras facing each other and a rectangular room, a temple overlooking the source and, outside the enclosure, a potable water cistern. The warm spring, which flowed to a depth of approximately 1.8 metres, was channelled into the valley by means of a duct sunk into the limestone rock. The duct was around 50 metres long and supplied a pond surrounded by a number of mosaic structures. Later, a monumental temple was erected above the well of the spring, and the court was extended with two monumental porticos built on either side. The spring itself probably proved insufficient or dried up, which led to a six-metre well being installed to provide access to the spring. Another duct was sunk to the same depth to carry warm water to the thermal baths. This phase dates to the final years of Hadrian and the rule of Antoninus Pius, while the first phase is Augustan. The titular deity of the temple remains a mystery.

About a hundred metres below the temple, a ramp that intersects with several flights of stairs led onto a porticoed plaza from the same period as the second phase of the temple’s construction. Thermal baths replenished by the warm spring backed onto the portico. As a result, what we have here is not the classic caldarium, but rather rooms supplied with water from a single warm source. It was not until the final phase that the complex was fitted with cold-water cisterns and also a frigidarium. There is evidence of several construction phases of the thermal baths, which are currently being identified and analysed.

Finally, at the foot of this monumental ensemble, there is a residence containing numerous mosaic floors, which, now restored, bears witness to the final phase of the site. By that time, the temple was being used as a baptistery for a basilica built to the north of the former place of worship. There is also evidence of a second church beside the thermal baths. In addition, houses were built on top of earlier structures.

The Franco-Tunisian archaeological expedition team that has been working on the site for five years is currently preparing the detailed map of the site, excavating previously unexcavated sectors and studying the relative chronology of the various sections. The Franco-Tunisian partnership, which was established for the study and exploration of this site, has set itself the goal of systematically bringing together and training young Tunisian and French researchers in fieldwork on, and the publication and restoration of, Jebel Oust.