The Bouleutirion (parliament house) is outside of the altis , just through the arch (modeled by Roman emperor Nero, who had his house just inside, built for his stay during the Games) and it was here that the competitors swore before a statue of Zeus to observe the rules.
From here the Vaulted Tunnel leads to the Stadium, through which only athletes and officials passed on the way to the competitions. The present Stadium was constructed during the 4th century BC with a track 212 meters long and the original starting blocks are still embedded in the clay. It accommodated 40 ,000 spectators, though there were actually no permanent seats-just artificial banks. There were also seats on the southern slope overlooking the Hippodrome (near the river) where the horse and chariot races were held. Seats were reserved for the rich folks, however, the ordinary people (including slaves and women) watched the events from the hill of Kronos to the north. Interestingly, the stadium's excavation was first carried out under the orders of Hitler, between 1941 and 1944. The German Institute further explored it from 1958-62 and restored it to its present form.
Outside of the Altis are the Gymnasium, the Palaestra where the athletes rested and prepared themselves, and the workshop of the 5th century BC sculptor Phidias who was in charge of the temple construction, and which later became part of a Roman basilika. The studio was built to the same dimensions as the 'cella' in which the statue of Zeus was to be placed, in order to achieve the exact lighting and final effect that the sculptor intended. The studio is part of a larger colonnaded building which was the Priest's House, the Theokoleion.
The Olympia Site museum (open Mon noon-7pm, Tues-Sun 8am-7pm; winter Mon 10:30am-5pm,Tues-Sun 8:30-5;6 euros admission). Sometimes signposted as the New Museum, it lies north of the sanctuary about 200 meters. Along with the Hermes of Praxiteles, the most famous of the individual sculptures is the Head of Hera, also dating from the 4th century BC and found in the Temple of Hera. The Nike of Paionos is larger--originally 10 meters high. There are some fine bronze items, including the Persian Helmet which the Athenians captured at the Battle of Marathon, and the helmet of Miliadhes who was an Athenian general; finds from the workshop of Pheidias, including the cup with his name inscribed; statuary and sculpture from the Temple of Zeus, the frieze of the Twelve Labors of Hercules ; and much more.