The Temple of Olympian Zeus(or Olympieion), is a large ruined temple in the center of Athens, which was dedicated to Zeus. Construction of the temple bagan in the 6th century, but it was not completed until the reign of the Roman Emperor Hadrian, some 650 years after the project had begun. It was at that time the largest temple in Greece. Originally there were 104 Corinthian columns of which only 15 remain standing.