Francesco Borromini

Francesco Borromini (1599-1667) was an architect born in Bissone, now in the Swiss canton of Ticino, the son of a stonemason. He trained as a mason, moved to Rome in 1619 and worked under Carlo Maderno at St. Peter's Basilica and Palazzo Barberini, continuing there under Gian Lorenzo Bernini after Maderno's death. His first independent commission was the church of San Carlo alle Quattro Fontane, begun in 1634.

Borromini laid out his plans from geometric figures such as triangles, ovals and stars. San Carlo, on a small corner site, has an oval dome lined with coffers, sunken panels in the shapes of crosses, octagons and hexagons, which get smaller toward the top, and a curving facade finished after his death. Sant'Ivo alla Sapienza (1642-1660), the church of Rome's university, is planned on a six-pointed star made of two overlapping triangles, and its lantern ends in a spiral. For the Oratory of Saint Philip Neri (1637-1651) he built a curved brick facade. At Palazzo Spada a colonnade about 9 meters long appears several times longer, because its floor rises and its columns shrink toward the far end.

For the Holy Year of 1650 he remodeled the interior of the Lateran Basilica, and from 1653 to 1657 he worked on Sant'Agnese in Agone in Piazza Navona, where later architects altered his design. He died by suicide in Rome in 1667.