The first Olympic Games at Olympia were held in 776 BC. They began as a religious festival, were held every four years, and continued for a thousand years. They were held in a sacred, fertile valley of Ancient Greece, in Olympia. Athletes came to Olympia and trained full-time for ten months. They had to undergo an examination by a ten-member panel, who assessed them on their parentage, character and physical endowments. As the games approached, thousands of spectators gathered in Olympia, transforming the little village into a thriving metropolis. At the first games in 776 BC, until 724 BC, the only event held was the stadium-length foot race (stade). The length of the race was based on the legend that Hercules, the god of Physical Strength, ran this distance in one breath. The earliest recorded winner at the Olympics was Coroebus of Elis, who won the 776 BC stade race. At later Olympiads, the "diaulos" (400 yards) and then the "dolichos" (3.3 miles) were added. In 680 BC, chariot racing appeared. The charioteers were professionals who raced over nine miles in the hippodrome. The winners, who lined up to receive the trophy, were the wealthy owners. Although women were barred from competing at the Games, they were sometimes declared winners because they owned the horses and chariots. The prize for victors at the Olympics was a simple olive tree branch, which was cut with a gold-handled knife, from a wild olive tree. The Greeks believed that the vitality of the sacred tree was transmitted to the recipient through the branch. The winning athlete gave public thanks to Zeus, and his home town or territory was considered in favour with the gods. When the Emperor Nero began his rule over the Greeks, the Games started to become a farce. The Romans, who were soldiers, converted the stadia into ampitheatres. Slaves competed in the place of free athletes. Their competitors were no longer noble opponents, but wild animals.