<P> One difficulty in dating the proto - Parthenon is that at the time of the 1885 excavation the archaeological method of seriation was not fully developed; the careless digging and refilling of the site led to a loss of much valuable information . An attempt to discuss and make sense of the potsherds found on the Acropolis came with the two - volume study by Graef and Langlotz published in 1925--33 . This inspired American archaeologist William Bell Dinsmoor to attempt to supply limiting dates for the temple platform and the five walls hidden under the re-terracing of the Acropolis . Dinsmoor concluded that the latest possible date for Parthenon I was no earlier than 495 BC, contradicting the early date given by Dörpfeld . Further, Dinsmoor denied that there were two proto - Parthenons, and held that the only pre-Periclean temple was what Dörpfeld referred to as Parthenon II . Dinsmoor and Dörpfeld exchanged views in the American Journal of Archaeology in 1935 . </P> <P> In the mid-5th century BC, when the Athenian Acropolis became the seat of the Delian League and Athens was the greatest cultural centre of its time, Pericles initiated an ambitious building project that lasted the entire second half of the century . The most important buildings visible on the Acropolis today--the Parthenon, the Propylaia, the Erechtheion and the temple of Athena Nike--were erected during this period . The Parthenon was built under the general supervision of the artist Phidias, who also had charge of the sculptural decoration . The architects Ictinos and Callicrates began their work in 447 BC, and the building was substantially completed by 432, but work on the decorations continued until at least 431 . </P> <P> The Parthenon is a peripteral octastyle Doric temple with Ionic architectural features . It stands on a platform or stylobate of three steps . In common with other Greek temples, it is of post and lintel construction and is surrounded by columns ("peripteral") carrying an entablature . There are eight columns at either end ("octastyle") and seventeen on the sides . There is a double row of columns at either end . The colonnade surrounds an inner masonry structure, the cella, which is divided into two compartments . At either end of the building the gable is finished with a triangular pediment originally occupied by sculpted figures . The columns are of the Doric order, with simple capitals, fluted shafts and no bases . Above the architrave of the entablature is a frieze of carved pictorial panels (metopes), separated by formal architectural triglyphs, typical of the Doric order . Around the cella and across the lintels of the inner columns runs a continuous sculptured frieze in low relief . This element of the architecture is Ionic in style rather than Doric . </P> <P> Measured at the stylobate, the dimensions of the base of the Parthenon are 69.5 by 30.9 metres (228 by 101 ft). The cella was 29.8 metres long by 19.2 metres wide (97.8 × 63.0 ft). On the exterior, the Doric columns measure 1.9 metres (6.2 ft) in diameter and are 10.4 metres (34 ft) high . The corner columns are slightly larger in diameter . The Parthenon had 46 outer columns and 23 inner columns in total, each column containing 20 flutes . (A flute is the concave shaft carved into the column form .) The roof was covered with large overlapping marble tiles known as imbrices and tegulae . </P>

The parthenon uses this type of column in its design