The Pillars of Hercules are on either side of the Strait of Gibraltar. The legendary Greek hero Hercules was said to have erected the Pillars on a journey to capture the Oxen of Geryon, a monster with three bodies who lived on an Atlantic island. Passing out of the Mediterranean he threw up the rocks on either side of the strait of Gibraltar. They were the Rock of Gibraltar and the headland on the Moroccan side.
Hercules’ journey was one of the 12 labours that the son of Zeus had been set by Eurystheus, king of Tiryns, whose servant he had become. One of the most famous of these labours was the cleansing of the Augean stables. So in-numerable were the herds of cattle that used these stables that, as they returned from pasture, they seemed to reach endlessly across the plain. Their stables were heaped high with manure and had not been cleaned for years. Hercules diverted the Rivers Alpheus and Pereus through them, and completed the task in one day.
For his last labour he braved the underworld to capture Cerberus, its three-headed watchdog.
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