While we toiled up the steep path that wound around the mountain. I saw the abbey. I was amazed, not by the walls that girded it on every side similar to others to be seen in all the Christian world, but the bulk of what I later learned was the Aedificium. This was an octagonal construction that from a distance seemed a tetragon (a perfect form, which expresses the sturdiness and impregnability of the City of God), whose southern sides stood on the plateau of the abbey, while the northern ones seemed to grow from the steep side of the mountain, a sheer drop, to which they were bound. I might say that from below, at certain points the cliff seemed to extend, reaching up toward the heavens, with the rock's same colours and material,, which at certain point became keep and tower (work of giants who lad great familiarity with earth and sky,. Three rows of the windows proclaimed the triune rhythm of its elevation so that what was physically squared on the earth was spiritually triangle in the sky.
As we came closer, we realised that the quadrangular form included, at each of its corners, a heptagonal tower, five sides of which were visible on the outside-four of the eight sides, then, of the greater octagon producing for minor heptagons, which from outsides appeared as pentagons.
And thus anyone can see the admirable concord of so many holy numbers, each revealing a subtle spiritual significance. Eight, the number of perfection for every tetragon; four, the number of the Gospels; five, the number of the zones of the world; seven, the number of the gifts of the Holy Ghost. In its bulk and its form, the Aedificium resembled Castel Ursino or Castel del Monte. which I was to see later in the south of the Italian Peninsula, but its inaccessible position made it more awesome than those, and capable of inspiring fear in - the traveller who approached it gradually. And it was fortunate that. since - it was a very clear winter morning. I did not first see the building as it appears on stormy days.