What is the diameter of the Parthenon's columns at their base in meters?

The Parthenon’s exterior columns measure about 1.9 meters in diameter at their base.

This measurement refers to the lower diameter of the large Doric columns in the outer colonnade. Architectural references commonly give an average of about 1.905 meters, conventionally rounded to 1.9 meters. The corner columns are slightly larger than the others, so the figure is best understood as a typical or average base diameter rather than an identical measurement for every column.

The columns rise approximately 10.4 meters, making their base diameter a strikingly large fraction of their height. Their shafts are fluted and taper upward, but the taper is not a perfectly straight reduction. A subtle swelling, known as entasis, gives the shafts a carefully controlled curve.

The diameter also participates in the temple’s broader proportional scheme. The spacing between column centres is about 4.293 meters, producing a diameter-to-spacing relationship close to 4:9. A frequent mistake is to answer with the column height or to confuse the exterior columns with the smaller interior supports. The question asks specifically for the base diameter of the outer Doric columns.