If you were visiting the ancient Olympics, you wouldn't see:
Women: The women were forbidden to participate in or even observe the games. Any woman discovered there could be thrown off a cliff! The women (young, unmarried ones) competed in a separate series of foot races called the Heraea, named in honor of Hera, the queen of the gods.
Water Sports: Despite miles and miles of beautiful coastline, water sports such as swimming were never a part of the ancient Olympic Games.
Team Games: In ancient Greece, each athlete competed on his own.
No World Records: No measurements were recorded of the length of a jump or javelin throw. Likewise, no times were kept for the running events. Winners' names might be recorded, however.