The Parthenon
In 437 BC, Mnesicles started building the Propylaea, a monumental gate at the western end of the Acropolis with Doric columns of Pentelic marble, partly built upon the old propylaea of Peisistratos. These colonnades were almost finished in 432 BC and had two wings, the northern one decorated with paintings by Polygnotus. Around the same time, south of the Propylaea, building started on the small Ionic Temple of Athena Nike in Pentelic marble with tetrastyle porches, preserving the essentials of Greek temple design. After an interruption caused by the Peloponnesian War, the temple was finished in the time of Nicias' peace, between 421 BC and 409 BC.
Construction of the elegant temple of Erechtheion in Pentelic marble (421–406 BC) was in accordance with a complex plan which took account of the extremely uneven ground and the need to circumvent several shrines in the area. The entrance, facing east, is lined with six Ionic columns. Unusually, the temple has two porches, one on the northwest corner borne by Ionic columns, the other, to the southwest, supported by huge female figures or Caryatids.
The Propylaea
The eastern part of the temple was dedicated to Athena Polias, while the western part, serving the cult of the archaic king Poseidon-Erechtheus, housed the altars of Hephaestus and Voutos, brother of Erechtheus. Little is known about the original plan of the interior which was destroyed by fire in the first century BC and has been rebuilt several times.
During the same period, a combination of sacred precincts including the temples of Athena Polias, Poseidon, Erechtheus, Cecrops, Herse, Pandrosos and Aglauros, with its Kore Porch (Porch of the Maidens) or Caryatids' balcony was begun. Between the temple of Athena Nike and the Parthenon, there was the Sanctuary of Artemis Brauronia (or the Brauroneion), the goddess represented as a bear and worshipped in the deme of Brauron. According to Pausanias, a wooden statue or xoanon of the goddess and a statue of Artemis made by Praxiteles in the 4th century BC were both in the sanctuary.
The Erechtheum
Behind the Propylaea, Phidias' gigantic bronze statue of Athena Promachos ("Athena who fights in the front line"), built between 450 BC and 448 BC, dominated. The base was 1.50 m (4 ft 11 in) high, while the total height of the statue was 9 m (30 ft). The goddess held a lance whose gilt tip could be seen as a reflection by crews on ships rounding Cape Sounion, and a giant shield on the left side, decorated by Mys with images of the fight between the Centaurs and the Lapiths. Other monuments that have left almost nothing visible to the present day are the Chalkotheke, the Pandroseion, Pandion's sanctuary, Athena's altar, Zeus Polieus's sanctuary and, from Roman times, the circular temple of Augustus and Rome.
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