located, with the Temple of Vulcan. The Olympeion complex' main attraction is the huge Temple of Olympian Zeus, which was described with enthusiastic words by Diodorus Siculus and mentioned by Polybius. Today it is reduced to ruins due to destruction begun in antiquity and continued through the 18th century, when the temple was used as a quarry for the port of Porto Empedocle. Near the south-western corner of the temples is a small edifice (12,45 x 5,90 m) with two naves and a deep pronaos, a double entrance and what has been identified as an altar. Its dating is controversial, though scholars have assigned it to the Archaic era, due to the discovery of numerous 6th century BC vases. Also archaic is another sacellum, which later was replaced by a classical edifice. These are followed by the scant remains of a temple (called "Tempio L") dating to the mid-5th century BC, measuring 41.8 x 20.20 meters, to which, in the 3rd century BC, a Hellenistic entablature was added. Temple of the Dioscuri North of Temple L is the "Temple of the Dioscuri," Castor and Pollux, the northwest corner of which is in a misleading modern reconstruction from the early 19th century, created using pieces from various other temples. It includes four columns and an entablature. The temple itself measures , and would likely have been a Doric peripteral with 6 x 13 columns, dating to about the mid-5th c. BC. Temple of Hephaestus On the other side of the valley is the last spur of the hill, commanded by the remains of the Temple of Hephaestus (also called the Temple of Vulcan), although the exact deity to whom it is dedicated is unknown. It is a Doric-style peripteral building measuring , mounted on a four-step crepidoma and having 6 x 13 columns; it dates to around 430 BC. It was built over an archaic sacellumm which measures . Its decoration, dating to ca. 560-550 BC, has been recently reconstructed. Other remains On the western side of the city are the remains of Gates VI and VII, the first probably lying on the road to Heracles, the second having two towers and two external bastions (one having 15-metre thick walls); northwards are the remains of Gates VIII and IX, now surrounded by illegal buildings. At the western tip of the area in which the Temple of Concordia lies, are parts of