The remaining Corinthian Columns of the Temple of Olympian Zeus, Athens. It is the largest temple in Greece, exceeding even the Parthenon in size. Work began on it in the 6th century BCE, during the reign of the tyrant Peisistratos, but was not completed for another 650 years when the Roman Emperor Hadrian dedicated it to Zeus Olympios during the Panhellenic festival of AD 132, on his second visit to Athens. Only 15 of the original 104 columns remain, each 17m high. The Corinthian capitals were added to the columns by a Roman architect in 174 BCE in place of the original Doric columns.