Slay the Nemean Lion and bring back its hide.

The first of Heracles' twelve labours, set by King Eurystheus (his cousin) was to slay the Nemean lion and bring back its skin.

Heracles wandered the areas until he came upon the town of Cleonae. There, he found a poor farm boy. This farm boy would sacrifice anything to get wealth. If Heracles slew the Nemean lion (who lived in a cave) and returned alive within 30 days of leaving, they would sacrifice a lion to Zeus, the god of all the ancient Greek gods. If he did not return within 30 days or he died, however, the boy would sacrifice himself to Zeus.

While he was looking for the lion, he made arrows to use against it, not knowing that it was impervious. When he found the lion, he started throwing arrows at the lion, but the lion wouldn't die. After some time Heracles made the lion return to his cave. The cave had two entrances, one of which Heracles blocked; he then entered the other. Because of the fact that the lion's skin was impenetrable, Heracles was forced to stun the beast with his club, before proceeding to strangle it. He then used the lion's own claws to cut off its pelt.

When he returned to the King, King Eurystheus was shocked. He gave Heracles the lion's invincible pelt to wear as a cloak, but warned Heracles that the tasks set for him would become increasingly difficult.

Heracles completed this task over the course of three months when he was eighteen years old.