Sant'Ivo alla Sapienza

Borromini's audacious Sant'Ivo alla Sapienza (1642-60) — built as the chapel of the original Sapienza University. The plan is based on a six-pointed star (a hexagon with alternating concave and convex curves), and the dome culminates in an extraordinary spiral lantern — visible from across the historic centre — which seems to twist itself toward heaven. The interior, sadly open only Sunday mornings 09:00-11:00, is a study in pure white geometric harmony. The courtyard outside is accessible during weekday business hours and offers a perfect head-on view of the spiral.