A section of Byzantine-era fortification walls survives on the western edge of the central park, a remnant of the late antique city that occupied this site between the fall of Roman power and the Arab conquest. The walls date from roughly the 5th–6th centuries AD, when Byzantine authorities sought to protect the remaining settled population from raids.
The ruins are not extensively excavated and are modest in scale compared with the Roman sites nearby, but they are accessible on foot from the park and add a layer to the city's long history that most visitors overlook. A sign in French and Arabic explains the site's context.