The two works by Borromini everybody quotes, San Carlino and Sant’Ivo, are whole churches he designed from the first stone. But half of his Roman output does not work that way: they are interventions inside buildings that already existed, and today you walk through them without knowing that part of what you are looking at is his.
There are four of them, they are all in the historic centre, and none of them costs anything to enter.
This article puts them in the order that makes sense, from the most famous to the one that closes the circle: the slab he is buried under.
Sant’Agnese in Agone, Piazza Navona
It is his most-seen work in the world, and almost nobody looks at it: people arriving in Piazza Navona photograph Bernini’s fountain and use the church as a backdrop.
The commission was not his. The church had been begun by Girolamo Rainaldi and his son Carlo for Pope Innocent X Pamphilj, who had the family palace next door and wanted a church facing onto the square. In 1653 the Pamphilj dropped the Rainaldis and called in Borromini, who stayed until 1657.
What changes, in four years of work on a building already set out by someone else? One thing, and you can see it from anywhere in the square: he takes a facade conceived flat and curves it inwards. The central section recedes, the sides come forward, and the dome behind it suddenly becomes fully visible, framed by the two bell towers he designed and others built.
The purpose becomes clear standing in the middle of the square: to make a narrow church, wedged between two palaces, look like the backdrop of a space seventy metres wide.
Inside, the plan is a Greek cross and the effect is vertical. If you have time, ask about the sacristy, which Borromini designed between 1658 and 1666 and which is the least visited part of the building.
Here, though, you should be wary of the friendliest guide on the square. The story of Bernini’s Nile covering its eyes so as not to see this facade is chronologically impossible: the fountain was finished in 1651, Borromini took over the site in 1653. I have told the whole story in the article on the Fountain of the Four Rivers.
Opening hours. Open every day except Monday from 9:00 to 19:00, closed between 13:00 and 15:00; on Saturday and Sunday it closes at 20:00. Free admission.
St John Lateran
This is the biggest commission of his life, and also the one that usually does not get credited to him, because a visitor walking into the cathedral of Rome is thinking of anything but the Baroque.
In 1646 Pope Innocent X gave him the remodelling of the basilica for the Jubilee of 1650. The problem he set is the kind that usually ruins a career: the basilica is the oldest and most venerable Christian building in the city, it has an early Christian layout with five naves and a sixteenth-century wooden ceiling, and nothing may be demolished.
How do you rebuild a basilica without touching it? The solution is visible in two seconds, if you know where to look. Borromini does not remove the ancient columns: he sheathes them. He encloses them inside twelve great piers, and in the piers he opens tabernacle niches, closed by pediments and columns of reused green marble.
The meaning is stated: the nave becomes the Heavenly Jerusalem of the Apocalypse, with its twelve gates. The statues of the apostles that now fill the niches, however, are neither his nor of his century: they were commissioned around 1702 and carved between 1704 and 1718 by Camillo Rusconi, Pierre Legros and others.
So for fifty years those niches stood empty. And that is why the vault Borromini had designed to cover the nave was never built: look up and you will still see the wooden ceiling he had been ordered to save.
Opening hours. Open every day from 7:00 to 18:30, free admission. The Cosmatesque cloister is paid separately.
Sant’Andrea delle Fratte
Between Via del Tritone and Piazza di Spagna, in a narrow street, stands the strangest building Borromini left in Rome, and most passers-by see it without stopping because the church’s facade is anonymous.
The piece is at the back. Between 1653 and 1665 Borromini built the drum of the dome and the bell tower, and left both in a condition with no equivalent: the drum was never covered by the planned cap, so what you see is a structure of bare brick, with diagonal buttresses forming a kind of St Andrew’s cross.
The bell tower, by contrast, is finished and brilliantly white: a circular drum of columns, above it a storey with four herms, and at the top a crown of wrought-iron flames over angelic heads. Look at it from below, from Via di Sant’Andrea delle Fratte, where it is wedged between the houses.
Inside the church there are also two angels by Bernini, the ones with the crown of thorns and with the INRI scroll: they are the originals he carved with his own hand for Ponte Sant’Angelo, considered too precious to be left out in the weather and replaced on the bridge by copies. I have written about them in the article on Bernini in Rome, palaces, angels and a last sculpture.
The two rival hands, in the same building, with no plaque explaining it.
Opening hours. The basilica normally opens in the afternoon, from 16:00 to 19:00 (until 20:00 on Sunday), with morning hours tied to services. Free admission. The bell tower and the drum can be seen from the street at any hour.
San Giovanni dei Fiorentini
The last stop is near the Tiber, at the start of Via Giulia, and it is the one that closes the story.
Here Borromini worked at the end of his life for the Falconieri family, who commissioned the main chapel and the altar. He also designed the family crypt beneath the sanctuary, an elliptical room with Doric columns and stuccoes: a space that, with an irony that reads as scripted, turned out to be unusable because of damp from the river.
But that is not why you come.
At the third pier of the left nave, on the floor, there is an octagonal slab of dark marble with a white oval at its centre. On it are two words and two dates: FRANCISCUS BORROMINI 1599-1667.
It is the tomb of Carlo Maderno, the relative who had brought him to Rome as a boy and taught him the trade, and it is there that Borromini asked to be buried when he died, on 2 August 1667. For almost three centuries his name was not on that slab: it was added in 1955.
It is worth reaching at the end of a walk begun in Piazza Navona. The man who built the most-seen facade in Rome lies under a floor almost nobody looks at.
Opening hours. The basilica is normally open in the morning and in the late afternoon; the Falconieri crypt has its own openings and has to be asked about inside the church. Free admission.
How to line them up in half a day
The four stops are not on the same line, so an order helps.
The short walk, two hours. Sant’Agnese in Agone in Piazza Navona, then ten minutes on foot to San Giovanni dei Fiorentini along Via del Governo Vecchio. These are the two that hold together best, because they are the beginning and the end.
The long walk, half a day. Add Sant’Andrea delle Fratte, on the other side of the centre towards Piazza di Spagna, and close with St John Lateran, the only one for which you need the metro (line A, San Giovanni stop).
Keep in mind. Sant’Andrea delle Fratte mainly opens in the afternoon and Sant’Agnese closes between 13:00 and 15:00: build the walk around the middle of the day and you risk finding two doors of four shut.
Practical information
Details checked on 30 August 2026 on the pages of the individual basilicas and on the Rome tourism board’s listings. Church hours change with services and with the season: check them the day before.
Tickets. None, in all four. The only paid things on this walk are the Lateran cloister and the guided visits to the crypt of Sant’Agnese.
How long. From two hours for the first two to a full half day for all four.
What to wear. These are working churches: shoulders and knees covered, and at the Lateran the entrance check is the one you would expect at a papal basilica.
The itinerary starts from the square beneath which the Stadium of Domitian still lies, which explains the elongated shape of Piazza Navona: it can be visited on a guided tour of the underground and is worth half an hour before you go into Sant’Agnese.
What to see nearby
The two churches Borromini built from scratch are San Carlino alle Quattro Fontane, open every weekday with cloister and crypt, and Sant’Ivo alla Sapienza, closed for restoration but with a courtyard you can walk into.
Five minutes from San Giovanni dei Fiorentini is Borromini’s perspective gallery at Palazzo Spada, the only paid thing on the whole Borromini trail.
For his relationship with the rival who competed with him for every commission, there is Bernini and Borromini and ten works by Gian Lorenzo Bernini.
These four churches are the free part of a wider route: the full itinerary of Borromini’s works in Rome brings in San Carlino, Palazzo Spada and the buildings that are closed.
Photo credits. Sant’Agnese in Agone: Jean-Pol GRANDMONT, CC BY 4.0. Lateran niche: Karelj, public domain. Bell tower of Sant’Andrea delle Fratte: GiulioTivoli, CC BY-SA 4.0. Borromini’s tomb: Pippo-b, CC BY-SA 3.0. All from Wikimedia Commons.
