Visible to the southwest of the Acropolis, is the Temple of Olympian Zeus. Construction began in the 6th century B.C., during the rule of the tyrant of Athens, Peisistratus. But construction was halted throughout the era of the Athenian Democracy, as the temple was deemed a symbol of tyranny. Later, during the Hellenistic period, there was an attempt to resume construction, by Antiochus IV Epiphanes, King of Syria, but work was once again terminated when he died. Still only half-finished, serious damage was inflicted on the Temple by Lucius Cornelius Sulla, who sacked of Athens in 86 B.C.
It was not until the accession of the Philhellene Emperor, Hadrian, in 131 A.C. that the project was finally completed, following its original design. The Temple was abandoned and badly damaged again, during the Herulian sack of Athens in the 3rd century, when most of the columns were torn down, to be used as building materials. Sixteen columns remain today, fifteen of them still standing and one lying on the ground, where it fell during a storm in 1852. Apart from the main temple, the site also contains remnants from Roman thermae, Classical era residences, foundations of an Early Christian basilica, and parts of the city’s Roman fortifications.
Source: www.athensattica.gr