At the spot where the stadium was built there is a natural concavity, between the foothill of Ardetus and the Ilissos river. Where the Ilissos river used to flow in antiquity now is V. Konstantinou Avenue. When constructing a stadium, or a theatre for the matter, every natural concavity is used for the areas where the audience sits. If you observe the seats of the stadium you will realize immediately why they constructed the seats at the particular part of the hill. The semi-circular section of the cavea (auditorium) exactly opposite the entrance of the stadium is called "sphedone". This stadium was constructed with marble from mount Penteli for the Panathenaea games, which took place every 4 years in honor of the goddess Athena. These games consisted of racing, wrestling, pankration and pentathlon. The ancient stadium had a capacity of 50,000 spectators. Herodes Atticus, the rich sophist who built the Odeum of Herodes Atticus as a gift to Athens, renovated the Panathenaic Stadium in 144 BC and covered it with marble from mount Penteli. The field was 204 meters long and 33,36 meters wide. The length of the distance that racers had to cover was approximately 600 feet. This track was defined within the field with landmarks in the form of steles bearing the busts of Apollo and Dionysus. You can see two such landmarks at the National Museum.
In the years of the Roman emperors the stadium used to be an arena where they fought with animals. The present day locker room (on the eastern side of "Spedona ") used to be an artificial tunnel for gathering the animals. Ardetus, the hill around the stadium, has a name with a very long history. The names Ardetus and Lycabetus are of Pre-Hellenic origin. The local hero of Attica, Ardetes, restored peace among the residents of Attica in a very turbulent period. At the top of Ardetus, Herodes Atticus had built a temple dedicated to the goddess Fortune, where they placed the gold and ivory statue of the goddess.