The Temple of Hephaestus or Hephaisteion (also "Hephesteum"; earlier as the Theseion (also "Theseum"), is a well-preserved Greek temple; it remains standing largely intact. It is a Doric peripteral temple, and is located at the north-west side of the Agora of Athens, on top of the Agoraios Kolonos hill. From the 7th century until 1834, it served as the Greek Orthodox church of Saint George Akamates. The building's condition has been maintained due to its history of varied use. After the battle of Plataea, the Greeks swore never to rebuild their sanctuaries destroyed by the Persians during their invasion of Greece, but to leave them in ruins, as a perpetual reminder of the war. The Athenians directed their funds towards rebuilding their economy and strengthening their influence in the Delian League. When Pericles came to power, he envisioned a grand plan for transforming Athens into the centre of Greek power and culture. Construction started in 449 BC, and some scholars believe the building not to have been completed for some three decades, funds and workers having been redirected towards the Parthenon. The western frieze was completed between 445–440 BC, while the eastern frieze, the western pediment and several changes in the building's interior are dated by these scholars to 435–430 BC, largely on stylistic grounds. It was only during the Peace of Nicias (421–415 BC) that the roof was completed and the cult images were installed. The temple was officially inaugurated in 416–415 BC.