From its beginnings the site was a sanctuary, with a permanent population limited to the temple priests. At first the games took place within the sacred precinct, the walled, rectangular Altis , but as events became more sophisticated a new stadium was built to adjoin it. The sanctuary, known as the Altis, consists of an unordered arrangement of several buildings. Enclosed inside the temenos are the Temple of Hera and Temple of Zeus, the Pelopion and the area of the altar, where the sacrifices were made. The hippodrome and later stadium were also to the east.
On the left, beyond some Roman baths can be found the Prytaneion and the Philippeion, as well as the array of treasuries representing the various city states. The Metroon lies to the south of these treasuries, with the Echo Stoa to the East. To the south of the sanctuary is the South Stoa and the Bouleuterion, whereas the West side houses the Palaestra(wrestling school), used by the competitors during their obligatory month of pre-games training, the workshop of Pheidias, the gymnasium and the Leonidaion, a large and doubtless luxurious hostel endowed for the most important of the festival guests.
Olympia is also known for the enormous ivory and gold statue of Zeus that used to stand there, sculpted by Pheidias, which was named one of the Seven Wonders of the Ancient World by Antipater of Sidon. Very close to the Temple of Zeus which housed this statue, the studio of Pheidias was excavated in the 1950s. Evidence found there, such as sculptor's tools, corroborates this opinion. The ancient ruins sit north of the Alfeios River and Mount Kronos (named after the Greek deity Kronos). The Kladeos, a tributary of the Alfeios, flows around the area.