Borromini’s San Carlo alle Quattro Fontane

Facade       Aerial picture       G.B. Falda surrounding San Carlo 1676

San Carlo alle Quattro Fontane
photo: Rome Dixit

San Carlo alle Quattro Fontane       Part of the facade

San Carlo alle Quattro Fontane  Facade
photos: Steven Zucker part facade: Carlo Raso

The San Carlo alle Quattro Fontane is named after the four fountains at the corners of the intersection of the Via Quirinale (the former Via Pia or Strada Pia) and the Via del Quattro Fontane (the former Via Felice or Strada Felice). The Spanish order of monks, the Trinitarians, tasked Borromini with designing a church and a monastery. Four fountains Wikipedia.

B. Falda ‘San Carlo alle Quattro Fontane’ c. 1670       Artist unknown ‘Quattro Fontane’
Piranesi Quattro Fontane    Lievin Cruyl ‘Quattro Fontane’ 1665    Cleveland Museum

Giovanni Battista Falda 'San Carlo alle Quattro Fontane'
Rijksmuseum, Amsterdam

The cardinal Barberini provided sufficient funding. The Jesuits would have been jealous of the eventual amount that the Trinitarians ended up having to pay: a measly twelve-thousand scudi. The Barberini’s had a palace that we’ll have a look a quick look at from the outside once we’re done here. It’s not without reason that Borromini was nearly awarded the order to also construct the Sant’Andrea al Quirinale. Wikipedia has more information about the San Carlo alle Quattro Fontane, and you can click here for 616 drawings of Borromini (Albertina Vienna).

The San Carolino (the small San Carlo) as this church is often called, quickly rises to prominence in Europe. Good engravings of this church were in high demand in the 16th century, but Borromini refused. The eulogy for the architect Borromini by the prior of this monastery has been preserved to this day. In it, he comments that the architect never wavered in personally supervising his own masons, sculptors, carpenters and smiths, whilst still keeping his work very affordable.

Borromini’s problem was that the lot that the monks purchased in 1611 wasn’t the most handy one in terms of size and shape. For instance, the width at the Via was only 24 metres. Too narrow, really, to construct a church and a part of the monastery. In addition, the corner where the old Via Pia and the Via Felice met wasn’t perpendicular. To make it worse, this cut-off corner had a fountain (Tiber) that wasn’t allowed to be removed. You will see how Borromini solved this in the most genius of ways. For example, he placed the living quarters of the monks, consisting of three floors, between the large courtyard and the church. And in turn, he placed the church and the stairs to the campanile in the cut-off corner (click here for a plan of the entire complex and Borromini’s map).

Facade    Middle part    Upper part    Map

San Carlo alle Quattro Fontane: facade bottom
photos: Steven Zucker

If you stand in front of the church, which was cleaned prior to the holy year 2000, you’ll see that the wall is built up from concave and convex wall spaces. This was also the case with Bernini’s church that we just looked at. Still, this wall is very different than the aforementioned. The middle convex shape follows the interior precisely. This does not apply to the two side bays next to the entrances. These concave shapes do however have the same curve as the semi-circle of the vestibule.

The facade was only completed after Borromini’s death by his cousin Bernardo. He was not afraid to implement some changes that he viewed to be improvements. Bernardo ordered Antonio Raggi, an assistant of Bernini, to sculpt an image of the holy Carlo Borromeo; an image that would be mounted on the wall right above the main entrance. Borromini would turn in his grave if he would ever see this sculpture of his greatest rival’s assistant.

Antonio Raggi ‘Carlo Borromeo’

San Carlo alle Quattro Fontane: Antonio Raggi 'Carlo Borromeo'
photos: Steven Zucker and Chris Nas

Both artists, Bernini and Borromini, didn’t really get along. This is true especially for Borromini. Both were brilliant in their fields, and their work resonates to this day. Their personalities could not have been more different. Gianlorezo Bernini is described by his contemporaries as a likeable man who got along with pretty much anyone. He was one of the few who actually enjoyed decent relations the arrogant French King Louis XIV. He had such close friendships to two popes, Urbanus VIII and Alexander VII, that he had unlimited to the Vatican. Bernini often left the pope’s room in the late nightly hours, and closed the curtains after they once again consulted about designs for squares and buildings. Next to being a sculptor, Gianlorenzo was also an architect, a painter, a poet, a playwright and a designer of intricate theatre decors.


The orders just kept flowing in. Bernini had a gallery with many assistants to satisfy the huge demand. As an architect, however, he was not well-versed enough in constructions. Then again, this was not entirely unusual in that time. Most architects were only really schooled in drawing before they got to the real work, like Bramante, Raphaël and Michelangelo.  

Borromini Cherub about 1620
Saint Peter middle portal

Francesco Castello, as Borromini was actually called, was a very different man. He was melancholic, nervous, suspicious and often fought with his clients. One day, he noticed how a young boy purposely damaged the marble blocks before the San Giovanni. Borromini made sure that his workers gave the boy a rough treatment. Too rough, because the poor boy died. Borromini was spared a life in prison because the pope intervened. After all, they needed him to complete the drastic renovation of the cathedral, the St. John Lateran, without any further delays. Borromini was originally a stonemason. Borromini was an expert in all kinds of complicated architectural constructions. When he ends up in Rome at age twenty, he first works as a decorator. When we visit the St. Peter, I’ll point out a decoration in the narthex above the middle portal (door of Filarete) that Borromini made.

Borromini Cherub 
Saint Peter middle portal
photo: David Macchi

When Bernini designs a tower for the wall of the St. Peters and it’s beginning to show cracks during construction, Borromini makes very detailed drawing (Albertina, Vienna) of the cracks (read more about the towers of Bernini here). He also draws a more slender tower that was able to be built without danger of collapsing. Borromini began to work for Bernini at age 25. Among other things he helped construct the Palazzo Barberini. Bernini likely made clever use of Borromini’s knowledge and designs. In any case, Borromini was wild with the idea of his designs being stolen. Prior to his suicide, he ended up burning many documents with designs and architectonic studies. Click here 616 drawings of Borromini (The Albertina museum,Vienna). Click here for Borromini’s account of his suicide attempt (he died one day later).

Entrance       Exit

photos: Steven Zucker
San Carlo alle Quattro Fontane nave
Wikipedia and entrance Steven Zucker

San Carlo alle Quattro Fontane    The entrance
Borromini’s geometric church plan

If you enter the church you’ll see how small it actually is. Borromini was for some time regarded as an architect with an anarchistic way of working. His designs and constructions allegedly arose ‘spontaneously’ (the Spanish architect Gaudi was also unjustly accused of this). Nothing could be further from the truth. Borromini worked in accordance with strict geometric patterns as can be seen in this church plan. Its design is extremely intricate. It is based on two triangles that are placed together. Two circles are drawn within, to then have an oval drawn around these two circles again. Lo and behold, we now have the floor pattern of the San Carlino. Once we’re there, I’ll use an A3 paper to further explain this system and demonstrate how he also based it on a stretched octagon.

San Carlo alle Quattro Fontane     Wall    Columns and entablature     Pavement
Main altar

San Carlo alle Quattro Fontane nave
photos: Lawrence O.P. Pavement: Steven Zucker Main altar: Chris Nas


San Carlo alle Quattro Fontane dome
photo: Carlo Raso

Reflection plan in the mezzanine below the dome geometric floor shape
Borromini’s study of the map    Dome    Lantern    Holy Ghost

San Carlo alle Quattro Fontane dome part walls
photos: Lawrence O.P. and dome: Steven Zucker Lantern: Chris Nas Holy Ghost: Alvesgaspar

We’ve already seen the vault decorations of this dome on Saturday afternoon, namely at the Santa Costanza. Borromini purposely derived his designs from this early 4th century mausoleum.

Geometric shape in the dome    Mosaics in the barrel vaults of the Santa Costanza
Dome and part of the walls     Emblem Trinitarian Order

San Carlo alle Quattro Fontane dome
photos: Fr Lawrence Lew, O.P. and Architas
San Carlo alle Quattro Fontane old refectory

San Carlo alle Quattro Fontane old refectory nowadays sacristy

After this church we’ll have a quick look in the sacristy and the small courtyard that can be found behind and to the right of the church. The refectory that serves as a sacristy nowadays is quite remarkable. In the round plaster corners, the architect opted to use squinches instead of pendentives (a term you still have to become familiar with). Squinches were used in the Middle Ages, but certainly not after the beginning of the Renaissance. These quirky elements led to Borromini having had a bad reputation for centuries. Squinches were used in the Middle Ages, but certainly not after the beginning of the Renaissance. These quirky elements led to Borromini having had a bad reputation for centuries.

Entrance to the courtyard       Courtyard

After the sacristy we’ll look at the small and oh so remarkable monastery court.
More pictures? click here. If you look closely, you’ll see very special details that deviate from the Vitruvian rules you’re familiar with. For instance, Borromini uses the Tuscan order, but at a closer glance it doesn’t quite feel right. The same goes for the architrave above these columns. Something outrageous takes place with the abacus of the Tuscan capitals. The balusters are also quite revolutionary, much more intelligent than the old shape. Borromini was heavily influenced by his hero Michelangelo when it comes to these things. We already discussed the unconventionalities of Buonarroti at the Porta Pia on Saturday afternoon. Giovanni Pietro Bellori (Wikipedia) called it a disgrace in 1664. Bellori did not mention Borromini by name, but everyone knew he was speaking about this anarchistic architect when he wrote the following:
“[…]  everyone imagines in his head a new idea or phantom of architecture in his own manner […] so that they deform buildings, even towns and monuments. They use, almost deliriously, angles and broken and distorted lines, they tear apart bases, capitals and columns with crowded stucco decoration and trivial ornaments and with faulty proportions, in spite of the fact that Vitruvius condemns such novelties.” Cited from: Anthony Blunt, ‘Borromini’, Cambridge, Massachusetts, London, Harvard University Press, 1979 p. 212.

San Carlo alle Quattro Fontane entrance courtyard exterior
photo: Alvesgaspar

Courtyard cloister    Ground floor    Corner      Side

San Carlo alle Quattro Fontane: Courtyard cloister
photos: Sailko

We continue towards the Palazzo Barberini.

Continuation Rome day 4: Palazzo and Piazza Barberini, Santa Maria della Concezione dei Cappuccini