Temple of Olympian Zeus
The Temple of Olympian Zeus is a former colossal temple located in the center of Athens. The construction of the temple started in the 2nd century AD and ended almost 7 centuries later, during the reign of Roman Emperor Hadrian. He also ordered to raise two large statues of Zeus and himself made of ivory and gold there.
Of course, the construction process had been periodically frozen because of various reasons. Aristotle, an ancient Greek philosopher, cited that this temple was a great example how tyrannies were involving people into such ambitious and difficult construction processes so that they did not have any time and energy to rebel.
The original temple with 104 columns stood only for a century and was destroyed by barbarians in the 3rd century AD. Later, it was used as a source of building materials for other buildings in Athens so nowadays only 15 of columns are standing and the sixteenth one lies on the ground. Unfortunately, the statues also have not survived until our days. However, even those sixteen columns are enough to imagine how the largest temple of Ancient Greece looked like.