Its surviving ruins and archaeological site are noted for their Hadrianic-era semi-subterranean housing, a protection from the fierce heat and effects of the sun.

It was notionally refounded at the time of its elevation to colony status and formally named Colonia Aelia Hadriana Augusta Bulla Regia after its imperial sponsor Hadrian.

Carthage gained control over the town during the 3rd century BC, when inscriptions reveal that the inhabitants venerated Baal Hammon and buried their dead in urns in the Punic style.

Under the Numidians, a regularized orthogonal grid street plan was imposed in the hellenistic manner on at least part of the earlier irregular system.

[4] The Romans assumed direct control in 46 BC, when Julius Caesar organized the province of Africa and rewarded the (perhaps simply neutral) conduct of Bulla during the recent civil war by making it a free city (Latin: civitas libera).

Drifting sand protected the abandoned sites, which were forgotten until the first excavations were begun in 1906, in part spurred by the destruction of the monumental entrance to the Roman city.

[5] Its small amphitheater, the subject of a reproach in a sermon of Augustine of Hippo, retains the crispness of its edges and steps because it lay buried until 1960–61.

[7] In the unique domus architecture developed in the city, a ground-level storey, open to the warming winter sun, stood above a subterranean level, built round a two-story atrium.