Bouleuterion of Ancient Olympia, Ancient council house in Olympia, Greece

The Bouleuterion of Olympia lies inside the Altis, south of the Temple of Zeus. Two apsidal halls of 30.79 m and 30.53 m frame a square courtyard 14.28 m on a side, entered from the east; a Hellenistic Ionic portico and a Roman Doric portico in the shape of a Greek rho were added later. A pedestal in the courtyard centre held the statue of Zeus Horkios.

Construction began in the sixth century BC and was completed in the fourth century BC; the Spanish source estimates a start between 668 and 572 BC. A Hellenistic Ionic portico was added on the east, and in Roman times a Doric portico shaped like the Greek letter rho was appended. The building housed the Elean Senate, which administered the Olympic Games.

The oath was sworn before a statue of Zeus Horkios, shown by Pausanias holding a thunderbolt in each hand, which he calls the image of Zeus best suited to frighten unjust men. A bronze tablet at the statue's feet carried an elegiac inscription warning against false oaths. The pedestal found at the centre of the square courtyard marks the spot.

The remains stand south of the Temple of Zeus within the sacred Altis enclosure of the archaeological site, making them easy to locate from the main sanctuary. Visitors will find the architectural layout straightforward to follow and understand from ground level.

Athletes registered for competitions, drew lots to determine pairings, and faced penalties for rule violations in these very chambers during ancient Olympic Games. The building served as both a ceremonial space and the working administrative center where the mechanics of the Games were managed.