The Cathedral of Saint Gorboduc, among its many wonders, is one of the few churches that features examples of diagonal architecture (Saint Fidgeta and Other Parodies; 34).
We've written before on the absurdity that is the Cathedral of Saint Gorboduc. We've also written (and jokingly pointed out) there were delays in its construction.
Bellairs writes in the third chapter of Saint Fidgeta and Other Parodies that the abnormality is "one of the great examples of how many different styles of architecture may blend into a frozen fugue of harmonious integrity." One such style he notes is diagonal, which includes "cross-purposed groining, crockets, finials, and imitation cane rood screens" that were thought to be of this style.
This is mere Bellairsian invention, of course. In English Gothic architecture there is a style and period known as perpendicular, so named for its emphasis on vertical lines. Bellairs spoofs this with a style more chaotic and susceptible to internal conflicts - something that easily describes the jumbled assembly of Saint Gorboduc's.
Also, there is no known proof that the cathedral's tour pamphlet was printed on souvenir dodecahedrons.