The Secret Lookout at the Top Of Sant'Ivo

Saint Ivo’s has the most spectacular vault in Rome. Francesco Borromini created the unusual nave by adding three lobes and three triangles to a hexagon, and then for the vault extended that shape all the way from the cornice to the lantern, where he suspended the Holy Spirit in the form of a dove.

On the exterior he used a Lombardian drum to absorb the thrusts of his dome, and then added his chimeric spire. The ziggurats of Mesopotamia and the Tower of Babel were his inspiration. For Borromini, wisdom’s chief attribute is charity, and charity is symbolized by flames. To this concept Borromini added the image of the three crowned papal tiara—the Pope’s charity in sponsoring the University would represent the Pope’s wisdom and charity.

Borromini added an observation deck at the request of Pope Alexander VII to accommodate visiting royalty who wanted to "go to the top." Staircases led to the loggia scoperta, then two flying buttress bridges went from the side wings to the roof, from north and south. Then the stepped roof on the drum gave ascent to the level of the lantern. The climbers crossed the bridge and reached the stepped vault, and then they had to walk along the base one quarter turn, then through the porticella "porta Pia" buttress to ascend the balustrade of the lantern, which had an opening on the front for this purpose. Borromini inserted a tiny well in one of the piers of the lantern, just three and one half palmi wide, which allowed the climber to ascend 37 iron clasps, reaching a chamber some ten and one half palmi square, right in the middle of the mass of the spire. Here the visitor had to step outside, if he was brave enough, and could walk along the spiral, using the curving path between the ridges of the crown, touching Borromini's stucco jewels and pearls. After three and one half turns, the visitor re-entered to reach a "manhole" three palmi wide and nine palmi high. Then as the visitor stood in this "well" he could pull himself up to situate himself in the "fiery travertine crown," with a fabulous view of the city. Ask your Bishop to get you an admittance!