Sant’Ivo alla Sapienza
Borromini fitted a church into the short end of the courtyard of Rome’s university. The plan is based on two equilateral triangles forming a star, and the walls swing alternately in and out. The lantern ends in a spiral twisting towards the sky.
The University of Rome, La Sapienza, had its building on the Piazza Sant’Eustachio, with a long courtyard by Giacomo della Porta. The church was to stand at the short end of the courtyard. Borromini was given the commission in 1632 as architect to the university, and the church itself was built in 1642–1660 under three popes. He worked with very limited space and wanted at the same time to create a church unlike any other. Bees from the arms of Pope Urban VIII and stars from those of Alexander VII appear in the decoration.
The plan starts from two equilateral triangles laid over each other to form a six-pointed star. The points end alternately in semicircular niches and pointed niches with curved ends, so that the wall undulates all the way round the room. The dome continues the same form without an intervening drum and becomes rounder towards the lantern. The interior is white, with few colours, so that form is what matters. Outside, the lantern rises with a spiral ending in a flame and a cross.
Borromini’s spatial solutions were daring, and many contemporaries thought they broke the rules. His geometry, in which simple figures are combined into complex spaces, influenced Baroque architecture in Central Europe, including Bohemia and Austria. Today the church is used by the university and for concerts, and the rooms around the courtyard house the State Archives. Sant’Ivo is regarded, together with San Carlo alle Quattro Fontane, as Borromini’s masterpiece.