This is true, only men, boys and unmarried girls were allowed to attend the Original Olympics, where male athletes competed in the nude. In fact, married women faced severe punishment if they were caught watching.
However, some events, like the chariot races in later Ancient Greek Olympics, were held outside of the sacred area so women could watch them. Women also had their own festival, which was also held once every four years. It was called the Heraea Games in honour of Hera the wife of Zeus
A married lady, called Callipateira, sometimes called Kallipateira, was caught at the men’s Olympics. She had disguised herself as a gymnastic trainer to watch her son, but got so excited that her womanhood appeared. However she was allowed to go unpunished as her father, her brothers and her son had all been victorious at Olympia. However, a law was then passed that compelled all trainers to strip before entering the arena!
The reason why adult women not allowed to attend was because Olympia was a sacred area dedicated to Zeus and was therefore sacred for men. Unmarried women were allowed to attend, as it was thought that the Olympics were a good place for young maidens to meet their future husbands!
To learn more about our show The Ancient Olympics – The Story of Callipateira where you can read two pages of script and hear two of the songs go to https://bit.ly/2RPJ1lm