The stadium is built on the natural slope at a higher level above the sanctuary of Delphi. Its entrance is on the eastern side, in the shape of a monumental propylon, formed by a triple arch with niche for statues within the two central arches. The top was formed in a stepped-out crop for privileged spectators. The first stadium was constructed in the 5th century BC and there were no seats for the public. It had a length of 180 meters for the main event that was running and lanes for 20 runners. Around the 2nd century AD, Herodes Atticus, the wealthiest Greek of the Roman period, sponsored the renovation of the stadium, giving the possibility to more than 6,000 spectators to enjoy the games. All Greek citizens were able to take part in the athletic events. There were many athletic games like foot races, physical contests, chariot and horse races that took place on the last day of the games at a different location. Until the 3rd century BC, the music competitions occurred in the stadium, but in the 2nd century BC they were transferred to the theatre. Conservation and restoration works have been carried out at the monument.