From Project Athinai
The Olympieion (temple of Zeus), the largest temple of Athens, was located on a low ridge to the east of the Akropolis. The south and southwest slopes of this ridge were rather steep.
The construction of the Olympieion began under the tyranny of the Pisistratides prior to 500 BC under the supervision of 4 architects: Antistates, Callaeschros, Antimachides and Porinos. The planned poros temple was supposed to be double peripteral in the archaic Doric order. Foundations were of limestone in the polygonal style and measured more than 40 by 100 m. The columns had a diameter of 2.42 m at the bottom and were 10 m high. Work on the temple was interrupted at the fall of the tyrants in 510 BC. By this time, only the foundations and several dozens of column drums had been made.
In 479 BC when the Athenians built the Themistoklean wall in a hurry, they used the column drums of the uncompleted temple as building material for the foundations of these new walls.
In 421 BC, only the foundations, some column-drums and an altar dedicated to Zeus probably stood on the site of the future temple.
The construction of the temple was resumed, with marble this time, in 174 BC by Antiochos Epiphanes. Work stopped once more at the death of Antiochos in 165 BC.
Finally, the Roman Emperor Hadrian completed the work in 132 AD.
Camp, John M.; The Archaeology of Athens, Yale University Press, 2001, pp. 6, 36
Connolly, Peter and Hazel Dodge; The Ancient City - Life in Classical Athens & Rome, Oxford: Oxford University Press, 1998
Travlos, John, Pictorial dictionary of Ancient Athens, Books that matter, New York, 1971, p. 402