The sanctuary at Sounion is one of the most important sanct-uaries in Attica.

While the site was likely inhabited in prehistoric times, the sanctuary is first mentioned in the Homer's Odyssey as the place where Menelaos stopped during his return from Troy to bury his helmsman, Phrontes Onetorides.

The finds of the 7th century B.C. are numerous and prove the existence of organized cult on two points of the promontory: at the southern edge where the Temenos of Poseidon was situated, and about 500 m. to the NE of it, where the sanctuary of Athena was established.