The Temple of Olympian Zeus, also known as the Olympieion, is a colossal ruined temple in the centre of Athens that was dedicated to Zeus, King of the Olympian gods.
Construction began around 550 BC by the tyrant Pisistratus, who envisaged building the greatest temple in the ancient world. The building was demolished after the death of Pisistratus and the construction of a colossal new Temple of Olympian Zeus was begun around 520 BC by his sons, Hippias and Hipparchos.
The work was abandoned when the tyranny was overthrown and Hippias was expelled in 510 BC.
The temple was left unfinished during the years of Athenian democracy, apparently because the Greeks thought it hubristic to build on such a scale.
In the treatise Politics, Aristotle cited the temple as an example of how tyrannies engaged the populace in great works for the state and left them no time, energy or means to rebel.
It was not until 174 BC that King Antiochus IV Epiphanes revived the project. The building material was changed to the expensive but high-quality Pentelic marble and the order was changed from Doric to Corinthian. However, the project ground to a halt again in 164 BC with the death of Antiochus. The temple was still only half-finished by this stage, and remained so until the reign of the Roman Emperor Hadrian in the 2nd Century AD, some 650 years after the project had begun. During the Roman period it was renowned as the largest temple in Greece and housed one of the largest cult statues in the ancient world.
The temple's glory was shortlived, as it fell into disuse after being pillaged in a Barbarian invasion in the 3rd Century AD. It was probably never repaired and was reduced to ruins thereafter. In the centuries after the fall of the Roman Empire the temple was extensively quarried for building materials to supply building projects elsewhere in the city. Despite this, substantial remains remain visible today.