The Erechtheion, Athens — built between 421 and 406 BC on the most sacred ground of the Acropolis, the site where Athena and Poseidon were said to have contested for the city's patronage. Its Porch of the Caryatids, where six marble maidens serve as columns, is one of the most copied architectural motifs in history.
© roger4336, CC BY-SA 2.0, via Wikimedia Commons
