The Nemean Games (Greek: Νέμεα or Νέμεια) were one of the four Panhellenic Games of Ancient Greece, and were held at Nemea every two years (or every third).
With the Isthmian Games, the Nemean Games were held both the year before and the year after the Ancient Olympic Games and the Pythian Games in the third year of the Olympiad cycle. Like the Olympic Games, they were held in honour of Zeus. They were said to have been founded by Heracles after he defeated the Nemean Lion; another myth said that they originated as the funeral games of a child named Opheltes. However, they are known to have existed only since the 6th century BC (from 573 BC, or earlier). The winners received a wreath of wild celery leaves from the city of Argos.
The various legends concerning its origin are related in the argumenta of the Scholiasts to the Nemea of Pindar, with which may be compared Pausanias, and Apollodorus. All these legends, however, agree in stating that the Nemean Games were originally instituted by the Seven against Thebes in commemoration of the death of Opheltes, later called Archemorus. When the Seven arrived at Nemea, and were very thirsty, they met Hypsipile, who was carrying Opheltes (Greek: Ὀφέλτης), the child of the priest of Zeus and of Eurydice. While she showed the heroes the way to the nearest well, she left the child behind lying in a meadow, which during her absence was killed by a dragon. When the Seven on their return saw the accident, they slew the dragon and instituted funeral games to be held every third year. Other legends attribute the institution of the Nemean Games to Heracles, after he had slain the Nemean Lion. The alternative tradition was that he had either revived the ancient games, or at least introduced the alteration by which they were from this time celebrated in honor of Zeus.