In contrast to the representation of the Olympian gods in the east pediment, in the west pediment the world of heroes and legendary ancestors is glorified with their depiction as judges of the divine word. The theme of the west pediment is the contest between Athena and Poseidon for the patronage of Attica. All the heroes and legendary first ancestors of Athens are in attendance in this scene, which takes place on Acropolis during the reign of the legendary king Cecrops. Athena won the contest, and according to myth, Poseidon flooded Athens in revenge - the water receding only after Zeusí intervention.
In the middle of the pediment, the two gods are depicted surrounded by their chariots. Their statues stand 3.30 meters tall. Athena is carrying a spear, helmet, garment and shield. The various inlaid ornaments of the statue were made of gold-plated bronze. Poseidon stands naked holding his trident. The contrasted motion of these two gods is balanced by the two pairs of horses tied to the godsí chariots, and their charioteersí struggle to restrain them. Iris, messenger of the gods, stands behind Poseidonís chariot while Hermes is behind Athenaís chariot. They have come to announce Zeusí desire to end the contest and the stem the flood caused by the revengeful Poseidon.
On the left side of the pediment, Cecrops appears with his daughter Pandrossos and his son Erysichthon alongside him. To the right, Amphitrites is depicted with Erechtheusí daughter Oreithyia, surrounded by her twin sons Zetes and Kalais. On the left side of the pediment, Cecrops appears with his daughter Pandrossos and his son Erysichthon alongside him. To the right, Amphitrites is depicted with Erechtheusí daughter Oreithyia, surrounded by her twin sons Zetes and Kalais. The reclining figures at the two ends of the pediments are personifications of the rivers Kiphissos and Kallirrhoe, and next to the latter, the river Ilissos is also depicted.