This Doric temple (5C B.C.) overlooks the Agora. Called the Theseion, it is in fact the Hehpaisteion: a worship place of Hephaistos. In the Byzantine epoch it became a church, then a cemetery until the last century. The sculptures evoke the adventures of Heracles and Theseus. The eastern portico still has its marble coffered ceiling. It leads to the naos, similar to a church nave with its portals and cradle vault dating from the 5C A.D. It is one of the best preserved Greek temples.