From Ward Perkins, Roman Imperial Architecture

Commanding the western end of Leptis Magna’s new forum, the gleaming marble Gens Septimia Temple was dedicated around 216 C.E. to worship of the emperor Septimius Severus. The temple was designed to impress. Built atop a double podium and approached by a dramatic, flaring stairway, it was fronted by striking red granite columns and enclosed on the remaining three sides by a green marble colonnade.