Designer:
Albert Samper
Unitat Predepartamental d'Arquitectura.
Universitat Rovira i Virgili.
Avinguda de la Universitat, 1
43204, Reus, Spain

The rose window on the main façade of Orvieto cathedral is unique because its design is based on a 22–sided polygon. It is well known that the icosikaidigon cannot be constructed using only a compass and a straightedge. This image is the result of the combination of some mathematical and architectonic concepts, developing the most accurate graphical method (geometrically and statistically) to the construction of this rose window.