The Temple of Olympian Zeus is an ancient Greek temple located in Athens, Greece. Also known as the Olympieion, it was built over several centuries starting in the 6th century BCE and was finally completed by the Roman Emperor Hadrian in the 2nd century CE.

The temple was designed to be one of the largest in the ancient world, with 104 Corinthian columns, each standing at a height of 17 meters. However, it was damaged by wars and earthquakes and only 15 of the columns remain standing today, along with some of the architrave blocks.

The temple was dedicated to the king of the gods, Zeus, and was built to house a colossal statue of the god. The statue, which was over 12 meters tall, was one of the largest of its kind in the ancient world, but was later destroyed or lost.

The temple was an important religious and political center in ancient Athens and played a significant role in the city's history. It was also the site of the Panathenaic Games, which were held every four years in honor of the goddess Athena.

Today, the temple is a popular tourist attraction and a significant landmark in Athens. Visitors can admire the remaining columns and the impressive size of the temple, and learn about its rich history and significance in ancient Greek culture.