This remarkable Attic pedimental composition of the early 6th century BC, belonged to an unidentified small building on the Athenian Acropolis. It represents Hercules defeating the Lernaian Hydra. The mythical hero uses a club, which he holds in his right hand, to attack the serpent-like monster with its nine terrible heads. To the left awaits Iolaos, Hercules's friend, ready to mount a chariot gripping tightly the horses' reins. A crab, the Hydra's ally, is depicted in the corner. Engraved details and brightly coloured paint once completed this relief. The decorative theme of Hercules and the Lernaian Hydra can be seen on several artefacts of the 7th century BC, from different areas of Greece. However, it first occurs in Attica in this monumental composition.