The twelve labours of Hercules or dodekathlon (Greek: δωδέκαθλον, dodekathlon) are a series of episodes concerning a penance carried out by Heracles, the greatest of the Greek heroes, whose name was later Romanised as Hercules. The episodes were later connected by a continuous narrative. The establishment of a fixed cycle of twelve labours was attributed by the Greeks to an epic poem, now lost, written by Peisander, dated about 600 BC.