Fossatum Africae ("African ditch") is one or more linear defensive structures (sometimes called limes) claimed to extend over 750 km (470 mi) or more in northern Africa constructed during the Roman Empire to defend and control the southern borders of the Empire in Africa. It is considered to be part of the greater frontier system in Roman Africa.
It is considered to have many similarities of construction to Hadrian's Wall, one of the northern borders of the Empire in Britain.
Capsa was a Roman colonia located in the south of modern-day Tunisia. Before Roman times Capsa was a center of the Capsian culture.
The Roman colonia was very important under the Roman emperors and reached 100,000 inhabitants at the end of the second century. Under the Byzantines the city was for some years the capital of the Byzantine province "Byzacena" and enjoyed a period of economic revival. General Solomon build in 540 AD a new city wall and named the city "Capsa-Justiniana".