Augean stables

In Greek mythology, the stables of Augeas, king of Elis in southern Greece. The yards, containing 3,000 cattle, had not been swept for 30 years. Heracles had to clean them as one of 12 labours set by Eurystheus, king of Argos; a feat accomplished in one day by diverting the rivers Peneius and Alpheus.

Augeas had promised Heracles a tenth of his cattle if he could complete the task in a day, but refused to honour the bargain when he discovered the hero's service to Eurystheus. Years later, Heracles took revenge by invading Elis.