It was Cyrenes harbor. Its name came from the (god) Apollo.
This harbor was well-known for exporting the medical plant (silvium) which played an important role in the economic life of Cyrene, to the extent that, it was stamped on its coin.
Its important ruins:

• The acropolis, on the southeast hill.
• The church of the three angles design.
• The Hellenistic theatre.
• Baths.
• The Byzantine palace.
• The city Hellenistic walls.

The old Greek port of Apollonia, has both the ruins and the village of Susa, as attractions. While modernisation of Libya, has reduced the number of traditional settlement, Susa still holds a lot of the past. Much of Apollonia has disappeared, due to landslides.
Apollonia served as the port of Cyrene, and the landscape between the two sites would alone defend the detour out here. Apollonia is a Greek settlement that is very much formed according to the topography, with a beach cut by rugged rocks, inland from it there are hills, all giving Apollonia a very nice setting. Apollonia has several churches, a small theatre carved into the rocks, public baths. Best preserved of Apollonia, are the walls.
The museum of Apollonia is small and friendly, but there will be more exhibited here when excavations of Apollonia are more completed. Still the acropolis remains unexcavated. There are also underwater ruins, that can only be explored by getting a trip with a local boat.

Going next
shahat (Cyrene) 20 km southwest