Cyrene is the great prize of Shahhat: a Greek colony that became a wealthy Roman city, spread across a ridge in the Jebel Akhdar. The site is large enough that you should think of it as a landscape rather than a single ruin.
The main route passes streets, houses, theatres, baths, and sanctuaries, with views opening over the surrounding valleys. It is less manicured than famous classical sites around the Mediterranean, which can make it more moving. You feel the distance, the weathering, and the vulnerability of the place.