The metopes on the back portray Herakles.

Less building took place during the 5th century BCE at Delphi; nevertheless some important works were produced. After their victory at Marathon (490 BCE) the Athenians built a Doric treasury in Parian marble in the Sanctuary of Apollo. It has been completely reconstructed and rivals the temples on the Acropolis at Athens in quality. The style of the metope relief sculpture featuring Theseus and Herakles is transitional and combines the freshness of Archaic art with the severity of Early Classical.