The port of Sabratha was established in 500 BC by the Phoenicians and became part of Roman territory in the 2nd and 3rd centuries AD.
From Schoder's lecture notes:
SABRATHA: Phoenician, on sea btw. 2 Syrta. Gk. Abrotomon; Rom. colony 1 c. AD.
b. Flavia Domitilla, Vespasian's wife.
Theater gen. to sea: c. 180 AD, for 5000
Theater stage. orchestra. Proscenium
Theater stage, looking up
Christian 4 c church apse mosaic