The Geometry of the Choir Plan in Suger’s Saint-Denis

  • I’m pleased to have this opportunity to address a session with such a strong geometrical component. I’m also happy to say that my geometrical work has given me a new perspective on Suger’s Saint-Denis, one of the most influential monuments in the history of medieval architecture. I believe that I now understand in reasonable detail the geometrical thinking that governed the east end of the church, whose ambulatory vaults are seen here. This pattern of vault ribs, of course, demands to be understood in the context of the structure’s overall plan.

Miletus- Market Gate

  • Make a square whose edges align with the axes of the central quatri-style block, and set it on the podium; its top edge will align with the column bases of the upper story. Call its side length 1.000.

    The distance between the inner column axes is then .500.

    Inscribe a circle in the square, along with its diagonals; this locates the base of the lower columns at height .147 and the lip of the lower cornice at height .854.

    Unfold the diagonals of the square to find the base of the upper entablature at height 1.414.