Chiesa di San Lorenzo

The Chiesa di San Lorenzo stands opposite Palazzo Reale in Italy, presenting a modest façade before its remarkable interior. Guarino Guarini reshaped the older church into a central-plan building. The Theatine priest, architect and mathematician gave the building its defining dome.

Construction began in 1634 and reached completion around 1680. The dome forms an engineered lattice, with a circular drum, eight windows and an octagonal lantern. Eight intersecting arches create an eight-pointed star, while smaller openings extend the geometric pattern.

Sunlight produces its most striking effects when the masonry and changing angles align. Around the spring and autumn equinoxes, noon light passes through the lantern and reaches the radial chapels. In the Cappella dell’Immacolata, the beam reveals a fresco of God the Father, while other rays illuminate Christ and souls in purgatory. Openings and shadows can also suggest the locally known “face of the devil”. Near the sacristy, a full-size copy of the Holy Shroud adds another focal point, with volunteers offering explanations.