The original Hippodrome was built in 203 AD by the Roman Emperor, Septimus Severus, when he rebuilt Byzantium. Constantine the Great reconstructed, enlarged, and adorned it with beautiful works brought from different parts of the Roman Empire when he chose Byzantium as his new capital. The Hippodrome was 117 m / 384 ft wide and 480 m / 1575 ft long with a capacity of 100,000 spectators. It is said that one quarter of the population could fit into the Hippodrome at one time.
The Hippodrome was destroyed and plundered in 1204 by the Crusaders.
During the Turkish period it lost its popularity, especially with the construction of the Blue Mosque. The ancient Hippodrome changed its name and became Atmeydanı (Horse Square), a place where Ottomans trained their horses.