The Temple of Hephaistos (God of fire) is located in the Ancient Agora in the centre of Athens. It is a Doric peripteral temple. It has a pronaos (fore-temple), inner shrine and opisthonaos (rear temple), the best preserved of its type in the Greek world. It occupies the crest of the Kolonos Agoraios Hill and was designed by an unknown architect in honour of Hephaistos, patron of metal-working and Athena Ergane, patroness of pottery and of crafts in general. It is built mostly of Pentelic marble.
The east side, which faces the Agora, received special attention, having ten metopes showing the Labours of Herakles, whilst the four easternmost of the metopes of the longer north and south sides depict the Labours of Theseus. Due to the last depictions the Temple has been named 'Theseion'.
Around 700 A.D. the temple was turned into a Christian church, dedicated to Saint George. Nevertheless, the last Holy Mass that took place in the temple was on the 2nd of February, 1833, during the celebrations for the arrival of King Otto in Greece. During the 19th century, after the capital of Greece moved from Nafplio to Athens in 1834, the site around the temple was used as a burial place for non-Orthodox Europeans, among whom were many philhellenes who gave their lives in support of the Greek War of Independence against the Ottoman Empire. After being a museum from 1834-1934, it has reverted to its current status, that of an ancient monument, where by extensive archaeological research was allowed.