No one is quite sure what the original function of the Basilique might have been, but it seems to have been built in the 4th century as some sort of storage depot for precious items such as silver and grain. Later on, probably under the Byzantines, it became a church. The structure was converted into a mosque in the 8th century in the wake of the Arab invasions. It houses a small collection of ancient stelae.
Opening hours are at the whim of the guard on site.