Intercolumniation

In architecture, intercolumniation is the spacing between columns in a colonnade, as measured at the bottom of their shafts. In classical, Renaissance, and Baroque architecture, intercolumniation was determined by a system devised by the first-century BC Roman architect Vitruvius. Vitruvius compiled standard intercolumniations for the three classical Greek orders, expressed in terms of the column diameter, twice the Vitruvian module, and he warned that when columns are placed three column-diameters or more apart, stone architraves break.

The standard intercolumniations are:

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