In 447 BC, the Athenian state launched a massive building project on the Acropolis to replace an older sanctuary destroyed by Persian invaders thirty years earlier. Pericles initiated this undertaking while the Delian League stood at its peak of power. Architects Ictinos and Callicrates began their work that same year, overseeing a team of skilled quarrymen who cut Pentelic marble blocks with iron tools like picks, chisels, and drills. The construction continued until 432 BC, though decorative work persisted until 431 BC. Slaves, foreigners, and Athenian citizens worked side by side for identical pay, performing specialized tasks ranging from stone cutting to carpentry. Temple building was such a rare craft in Greece that these workers traveled from distant regions to Athens to assist. The structure rose upon the euthynteria and krepis of its precursor, which had been left as a ruin for over three decades after the sack of 480 BC. Archaeological excavations between 1885 and 1890 revealed drums of columns from the earlier temple embedded within the curtain wall north of the Erechtheion. Wilhelm Dörpfeld identified this substructure as Parthenon I, noting it consisted of two steps of Poros limestone topped by a Karrha limestone layer now covered by the final foundation. The delay in rebuilding likely stemmed from an oath sworn by Greek allies before the Battle of Plataea in 479 BC, which forbade reconstruction of sanctuaries destroyed by Persians. That oath remained binding until the Peace of Callias in 450 BC absolved the Athenians from their vow.
Architectural Design And Refinements
The architects chose an octastyle Doric design featuring eight columns across the front instead of the traditional six found in typical temples. This decision addressed the challenge of scale while maintaining structural stability and aesthetic harmony. Seventeen columns line each side of the building, creating a ratio of four to nine that appears throughout the elevation and column spacing. Optical refinements were woven into every dimension to counteract visual distortions perceived by the human eye. The stylobate curves upward at its center by 10.3 centimeters over a span of 70 meters, forming a subtle ridge visible on the capitals. Columns exhibit entasis, swelling slightly near the base and tapering toward the top with a ratio between one five hundredth and one six hundredth. Both the columns and naos walls incline inward slightly, while corner columns are displaced to correct perspective errors. These adjustments reflect theories proposed by Francis Penrose in 1851 regarding convex corrections for concave silhouettes. Scholars debate whether these deviations served drainage purposes or purely aesthetic goals. The architects also resolved the contraction problem by varying metope lengths between 1.175 and 1.37 meters to ensure frieze ends aligned correctly at corners. No ancient text survives describing their methods, yet modern research identifies recurring units like 858 millimeters underlying main dimensions. Anne Bulckens suggests this measure preserves the characteristic nine to four proportion while revealing additional ratios related to Pythagorean musical scales.