Constructed primarily of fine Pentelic marble between 421 and 406 BC, this grand portico of the Erechtheion features six soaring, finely fluted Ionic columns arranged with four across the front and two behind. They are celebrated for their exceptionally detailed scroll-like capitals (volutes). The structure serves as the monumental entrance leading into the western chambers of the asymmetrical temple, which was dedicated jointly to Athena Polias, Poseidon, and the mythical king Erechtheus.