On the bottom right of this image stands the iconic, circular Tholos of Delphi within the Sanctuary of Athena Pronaia, while the stone terraces of the 4th-century BC Ancient Gymnasium cascade down the left hillside of Mount Parnassus. At the bottom left is the Cold Pool on the palaestra (the lower terrace of the training grounds), measuring roughly 10 meters (33 feet) in diameter and nearly 2 meters deep. This circular outdoor plunge pool was fed directly with fresh running mountain water for the athletes to wash off and cool down.