Discover Sant'Ivo alla Sapienza

Sant'Ivo alla Sapienza stands inside the small courtyard of the Palazzo della Sapienza, which housed the University of Rome from the fifteenth century until 1935. Francesco Borromini built it between 1642 and 1660, consecrated in 1660, adapting his design to a palace already designed and partially built by Giacomo della Porta — the church closes the end of what is still called della Porta's courtyard.

The dedication is to Saint Ivo, patron saint of jurists, which is the obvious choice for the church of a university; the altar painting shows him. The plan resembles a star of David, which the reference work says would have been recognised at the time as a Star of Solomon, symbolising wisdom, and it is built from curves and clipped triangle tips rather than from straight bays.

Above it rises a polylobed dome and a cuspidate lantern that spirals, surmounted by a cross and carrying a sphere and a dove with an olive branch, in wrought iron. Borromini designed the floor too, in black and white marble intarsia, and the interior's effect comes from what Turismo Roma calls its animated plan and the upward thrust of its pilasters.

The decoration records who paid: the bees of the Barberini, for Urban VIII, with the dragons of the Boncompagni, the eagles of the Borghese and the stars and mounts of the Chigi. The altarpiece was started by Pietro da Cortona in 1661 and completed by his pupil Giovanni Ventura Borghesi, which Turismo Roma dates to 1683.

A plan that is a diagram, carried all the way to the roof. Borromini chose a floor resembling a star of David, which the reference work says would have been recognised at the time as a Star of Solomon, symbolising wisdom — precisely the right emblem for the chapel of a university. Turismo Roma calls the plan mistilinea, a six-pointed star, and the geometry is built from curves and clipped triangle tips alternating round the room rather than from straight bays.

What makes the building extraordinary is that he does not abandon that geometry at cornice height. The polylobed dome carries the alternating points and lobes upward, so the star is still legible when you look straight up: plan and vault are one idea at two heights. The interior's energy, in Turismo Roma's phrase, comes from its animated plan and the upward thrust of the pilasters, which gather the eye into the dome rather than ringing the walls.

The lantern is the famous part: a cuspidate form that spirals, surmounted by a cross and carrying a sphere and a dove with an olive branch in its beak, all in wrought iron. Wikipedia's whole judgement on it is that the corkscrew lantern of the dome was novel; nothing else in the city looks like it.

The setting was not his. The church sits at the end of Giacomo della Porta's courtyard, and Borromini merged a curved facade with it rather than building a front. Inside, the floor is his own design in black and white marble intarsia, and the decoration carries the bees of the Barberini — Urban VIII's flying bee is set in the lantern roof — with the dragons of the Boncompagni, eagles of the Borghese and stars and mounts of the Chigi.

Eighteen years, inside a palace that was already half there. Borromini broke ground in 1642 and finished in 1660, and the constraint shaped the result: the Palazzo della Sapienza had been designed and partially built by Giacomo della Porta, and the church had to complete it.

That is why the facade curves. Rather than build a front, Borromini merged a curved church facade with the courtyard, so the two read as one composition and the church becomes the end of a court instead of an object on a street. The width of the building was effectively decided before he started, and Turismo Roma describes the courtyard it stands in as small.

The star plan is the answer he found inside that constraint: a centralised geometry of curves and clipped triangle tips that needs no street frontage to make sense, and that can be carried upward through a polylobed dome without a conventional drum. The spiral lantern is the last move, and the only part of the building that escapes the courtyard entirely — it is what the surrounding streets see.

The money is recorded in the fabric. Urban VIII Barberini patronised the work, and Borromini set the family's flying bee in the roof of the lantern. Consecration came in 1660; the altarpiece followed, started by Pietro da Cortona in 1661 and completed by his pupil Giovanni Ventura Borghesi after Cortona's death, dated by Turismo Roma to 1683.

Can I get inside? No visiting hours are published. Turismo Roma names only Mass Monday to Friday at 09.00 in the Sala della rettoria, with entry from Corso del Rinascimento 40 and Via del Teatro Valle 33, and says that on Sundays and holidays entry is allowed only from Via del Teatro Valle 33. Plan for the exterior.

What is the spiral thing on top? The cuspidate lantern of the dome, which spirals upward and is surmounted by a cross, carrying a sphere and a dove with an olive branch in wrought iron. Wikipedia says simply that the corkscrew lantern was novel.

Why is the plan a star? Borromini chose a plan resembling a star of David, which the reference work says would have been recognised at the time as a Star of Solomon, symbolising wisdom — the emblem for a university church.

Who built it and when? Francesco Borromini, from 1642 to 1660, consecrated in 1660, completing a palace designed and partly built by Giacomo della Porta.

Who is Sant'Ivo? Saint Ivo, or Yves, patron saint of jurists — Turismo Roma calls him the patron of lawyers. Either way, the right saint for the church of the University of Rome.

Who painted the altarpiece? Pietro da Cortona started it in 1661 and his pupil Giovanni Ventura Borghesi completed it after Cortona's death; Turismo Roma dates the completion to 1683.

Whose bees are those? The Barberini, for Urban VIII, who patronised the work — Borromini set the family's flying bee in the roof of the lantern.

Does it cost anything? No price is published.