The corkscrew spire is a remarkable sight, rising out of the six-point star floor-plan courtyard that merges with the façade in a rhythmic, almost hallucinogenic whirl. Rising along the base of the dome’s pillars is the papal Chigi family emblem of the six mountains beneath a star, leaving their stamp of patronage. Unfortunately the church is only open on Sundays, but if you do manage to get inside look for Pietro da Cortona’s altarpiece depicting Saint Yves, to whom the church is dedicated. You can, however, see the exterior at anytime from the courtyard (which also doubles up as a dazzling suntrap at lunchtime) off Corso Rinascimento. Look in while you’re passing and stop with a slice of pizza – it’s well worth the head-spin.