For his fifth labor, Eurystheus commanded that Hercules clean the filthy cattle stables of King Augeas [O-gee-as] in one day. This was a monumental task as the stables had not been cleaned in ages and they housed the largest animal herd in all of Greece. Hercules made an agreement with Augeas whereby the king would give the hero one tenth of his cattle if he was able to clean out the stables in one day. He did not tell the king of his arrangement with Eurystheus.
Augeas sent his son Phyleus to witness the work as he had witnessed their agreement. Hercules set about his enormous mission by punching a hole in the wall at one end of the stable and then another in the wall at the other end. He then dug two trenches which diverted the course of two different rivers. These diversions brought their waters rushing through the stables, cleaning out the years of muck and mire. He completed the task by repairing the holes in the stables and returning the rivers to their original course.
Augeas reneged on his promise to give one tenth of his cattle to Hercules, even though the job was accomplished on a single day. A judge was called in to settle the dispute. Phyleus testified to the agreement and the judge granted Hercules his due reward. Upon his return to Tiryns, he learned that Eurystheus would not accept this labor because he was paid for it. Instead of six more labors, Hercules was still faced with seven more.