Discover San Carlo alle Quattro Fontane

San Carlo alle Quattro Fontane — San Carlino to Romans — stands at the crossroads of four fountains on the Quirinal, and was Francesco Borromini's first independent commission. He received it in 1634 under the patronage of Cardinal Francesco Barberini; Turismo Roma records that the church and convent were entrusted to him by the Spanish Trinitarian fathers and that he worked on them in a first phase from 1638 to 1642, while the reference work dates that construction 1638-1641. It was dedicated to Saint Charles Borromeo in 1646.

The interior is dominated by what Turismo Roma calls a splendid elliptical dome, decorated with stucco coffering in the form of hexagons, octagons and crosses — coffering that, the reference work adds, is deep-set, interlocking, and diminishes in size the higher it rises. The church is small: sixty-six feet wide and thirty-nine feet long.

The serpentine facade was conceived early, probably in the mid-1630s, but built only toward the end of Borromini's life, and its upper part was completed after his death in 1667; work continued under his nephew Bernardo until 1682. Beside the church is a two-storey cloister on an octagonal plan, and beneath it a crypt that follows the church's own size and form under a low pierced vault.

Open for visits on weekdays, 10.00-13.00 and 15.00-17.00 from October to April, 16.00-19.00 from May to September, with Mass on Sundays and solemnities at 11.00. The church states that entry is free and that a visit takes in the church, the sacristy, the cloister and the crypt; it gives its own capacity as about 45 people.

A dome that lies about its own height, on purpose. The coffering is deep-set and interlocking — octagons, crosses and hexagons — and it diminishes in size the higher it rises. Shapes that shrink as they recede are how a painter fakes distance, and Borromini built it: the oval is modest and reads as soaring. Turismo Roma describes the same pattern from the other side, calling it a splendid elliptical dome elegantly decorated with stucco coffering in hexagons, octagons and crosses.

The facade waves, and it waves because of where it stands. The site is the corner of a crossroads with a fountain in each angle, which gives a building no good square view of itself. The serpentine front answers that by curving in and out so that it presents a changing face to anyone approaching along either street. It was conceived in the mid-1630s and built only at the end of Borromini's life, with its upper part completed after his death — so the front is his earliest thought and his last work at the same time.

The cloister is the quiet masterpiece. Turismo Roma calls it a masterpiece of harmony and proportion, on two levels, on an octagonal plan; the reference work notes the same two-storey arrangement. Cutting the corners off a rectangle removes every sharp turn, and a very small courtyard stops feeling small.

Underneath, the crypt repeats the church. It follows the size and form of the church above and has a low pierced vault — the same oval, pressed flat.

Forty-eight years from commission to completion, and the architect was dead for the last fifteen. That span is the building's real history.

Borromini took the job in 1634, at the start of his independent career, for the Spanish Trinitarians — an order without the means of the families who employed Bernini. The constraint shows as invention rather than poverty: the material is stucco and stone, not marble and gilt, and the effects are got from geometry, depth of cut and light.

The church went up between 1638 and 1641 — Turismo Roma says the first phase ran to 1642 — and was dedicated in 1646. The dome was the problem worth solving: an oval in a tight corner, which Borromini filled with interlocking coffering that shrinks as it rises so the eye reads more height than exists.

The facade came last and latest. Conceived in the mid-1630s, it was built only toward the end of his life, and the upper part was not completed until after he died in 1667. His nephew Bernardo carried the work on until 1682. The man who designed the front never saw the top of it.

When is it open? Weekdays 10.00-13.00, then 15.00-17.00 from October to April and 16.00-19.00 from May to September. Mass on Sundays and solemnities at 11.00; groups may request access outside those hours.

Does it cost anything? No. The church states plainly that entry is free and that a donation toward maintenance is welcome. That covers the sacristy, cloister and crypt as well.

Is this Borromini's first building? The reference work calls it his first independent commission, received in 1634 under Cardinal Francesco Barberini.

When was it built? 1638-1641 according to the reference work; Turismo Roma gives the first phase as 1638-1642. Dedicated to Saint Charles Borromeo in 1646. The page gives both readings.

Did Borromini see it finished? Not the front. The serpentine facade was built at the end of his life and its upper part was completed after his death in 1667; his nephew Bernardo continued until 1682.

Why does the dome look so tall? The coffering is deep-set and shrinks as it rises, which is how a painter fakes depth. The church is only sixty-six feet by thirty-nine.

Can I see the cloister? Yes — Turismo Roma names it as part of the church and calls it a masterpiece of harmony and proportion, on two levels and an octagonal plan.

What is across the road? Bernini's Sant'Andrea al Quirinale, at number 30 against this church's 23.