The small sanctuary of Poseidon is located within the fortified port town of Sounion; on a rocky peninsula 69 km SE of Athens. Inside the temenos a stoa stands along the N and W precinct wall. The temple of Poseidon occupied the center of the precinct. North of the sanctuary is a smaller sanctuary dedicated to Athena Sounias. The town of Sounion was a port of call for Athenian grain ships from Euboea and the sanctuary of Poseidon served as a refuge for slaves escaping from the Laurion silver mines.