San Carlo alle Quattro Fontane historical timeline

A young architect's first job, on a difficult corner, for an order with no money — and the building that made his name.

Chronology

1. 1634 — Borromini receives the commission, under the patronage of Cardinal Francesco Barberini. The reference work calls it his first independent commission. Structural impact: a cramped corner site at a crossroads sets every constraint that follows. What you see today: a church that meets you at an angle because it never had a frontage to meet you square.
2. Mid-1630s — the idea for the serpentine facade is conceived, though not yet built. Structural impact: the undulating front is designed decades before it is executed. What you see today: a facade that is early Borromini as an idea and late Borromini as stone.
3. 1638-1641 — the church is built. Turismo Roma gives this first phase as 1638 to 1642; the reference work gives 1638 to 1641. Structural impact: the oval, the dome and its interlocking coffering are set. What you see today: the white room and the dome above it.
4. 1646 — the church is dedicated to Saint Charles Borromeo. Structural impact: none. What you see today: the name, and the Trinitarian crosses worked into the stucco.
5. Late in Borromini's life — the facade is finally constructed. Structural impact: the waving front arrives thirty years after it was imagined. What you see today: the only part of the building its architect did not live to see finished.
6. 1667 — Borromini dies, with the upper part of the facade incomplete. Structural impact: the work passes to his nephew Bernardo. What you see today: an upper storey finished by another hand.
7. 1682 — construction continues under Bernardo until this year. Structural impact: the complex is completed forty-eight years after it was commissioned. What you see today: the finished crossroads corner.

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