During the fifth century B.C., Greek architects perfected a method for designing Doric peripteral temples, and this procedure was used for most temples constructed during the second half of the century in mainland Greece and in its colonies. This procedure had to be determined in order to see how it was adapted to design the Parthenon. Minor modifications enabled the architects of the Parthenon to achieve greater commensurability than for any other Doric temple (Fig. 1).
To lay foundations for a Doric temple, an architect needed to know the number of columns and the overall length. Since nearly all peripteral temples of the Doric Order have six columns on their fronts, the first decision which ordinarily needed to be made was how many columns would be used on the sides, and for hexastyle temples this ranged from ten to sixteen columns. The ratio of the number of columns on the fronts to the number on the sides determined the overall form and was the single most important ratio which had to be selected. The column number ratio was reused as the ratio for the stylobate of some of the earliest stone temples (Table 1, column 2; Table 2, column 6), and it was later applied to the krepis. It was used as the ratio of the krepis for the great majority of temples constructed from c. 535 and c. 320 (Table 1, column 1; Table 2, column 4).