It was a peripteral hexastyle, and must have had at least nineteen columns at the sides; the portion excavated shows that its total width is 744 ft., the width of the cella 382 ft., the lower diameter of the columns 64 ft.

The temple is a Doric peripteral hexastyle in antis, with 13 columns at the sides; its length is 104 ft., its breadth 452 ft., its height, to the top of the pediment, 33 ft.