Why you must see the Dome illusion in Rome

Among its artwork and ancient ruins, the “eternal city” holds many secrets and optical illusions created to perfection by masters of the past.

When in Rome you can admire some of these stunning artworks, you will stumble across the magical perspective of Via Nicolò Piccolomini and Bernini’s artwork at Palazzo Spada, without forgetting the Pantheon and St. Peter’s square optical illusions!

But there is more! In Rome you can even find a fake dome, as in the Church of St. Ignatius of Loyola. If you are wondering why you must see the Dome illusion then read on.

The Church of Saint Ignatius of Loyola



View of the Church by Tetrakyts – Wikimedia Commons

A stone’s throw from the Pantheon along Via del Caravita, you can admire the Church of Sant’Ignazio da Loyola also known as “Sancti Ignatii de Loyola in Campo Martio“.

Is part of the ancient complex known as Collegio Romano, which includes many classrooms, refectories, laboratories and kitchens, stables and a chicken coop, dormitories, workshops and the astronomical observatory of Athanasius Kircher.

It was built between 1626 and 1685 at the behest of Cardinal Ludovisi, to replace the old “chapel of the Annunziatina”, which could no longer contain two thousand students.

In 1649 the works at the great sanctuary were almost finished, but Father Antonio Sasso and Father Orazio Grassi found themselves in difficulty. The dome had to respect the proportions of the structure, but the Jesuits were broke and the inhabitants were not happy about the construction of a very huge dome.

For this reason the works were suspended, the church had a flat ceiling and no dome. Until 1679, when the painter and architect Antonio Pozzo proposed to create a fake dome inside the Church that would fool the eyes of visitors.

The layout of the Church


Layout of the Church by Franco Ravelli – Wikimedia Commons

The Church of St. Ignatius of Loyola is a classic example of Italian Baroque style. Inside this wonderful church you will find a nave that is 43 meters wide and 81.5 meters long with a typical Latin cross shape, an apse presbytery and six side chapels, three of which are on the left and three on the right.

The six chapels located along the side aisles make the whole church much more harmonious. Here you will find represented different scenes from the life of Saint Ignatius, such as the defense of Pamplona, where Ignatius was wounded.

Outside, the façade designed by Carlo Maderno is divided into two orders. In the lower one there are three openings that allow access into the Church, with doors surmounted by tympanums embellished with refined festoons. While in the upper part you will see a large window flanked by two volutes and surmounted by a large tympanum.

My top tip

Once here in the church, you absolutely have to see the rooms known as “the bedrooms of San Luigi Gonzaga“, rooms that were once inhabited by the Jesuits and recently renovated. If you want more information click here, you will find the entire story of Luigi Gonzaga and about the rooms!

The optical illusions


Frescoes by LivioAndronico2013 – Wikimedia Commons

Once inside, the wonder will accompany you throughout the visit. You will notice the floors that have particular geometries of marbles that lead to the centre of the nave.

You will reach the first point marked on the ground with a circle, to admire the perspective simulation of a second temple, superimposed on the first, the real one.

Through the effect known as “quadramento“, Pozzo created a simulated architecture, readable in perspective “from below” and articulated on two orders, one lower and one higher. Columns, arches and entablatures frame the representation of the “Glory of Saint Ignatius”, with Christ holding the cross and a beam of light that illuminates the Saint and the four allegorical figures representing four continents.

The fake dome


The fake dome by LivioAndronico2013 – Wikimedia Commons

A little further on, towards the altar you will find a golden disk on the ground. From here you will admire the formidable frescoes made by Pozzo and which manage to transform a flat surface into the hollow of a dome with 13 meters in diameter.

The technique used by the famous author is the trompe-l’oeil (which means “deception of the eye”). If you move from that point, the dome takes on a completely different perspective, losing the three-dimensional effect.

My top tip

The best way for you to view the illusion is to enter inside the church keeping your eyes low until you reach the marble circular point which indicates the best place to admire the first outstanding optical illusion.  The second marker on the floor will indicate the ideal viewing spot for the dome.

The entrance is located in Piazza Sant’Ignazio.
The church is open from Monday to Saturday: 7.30 – 19.00 (last admission 18.50) and on Sundays from 9.00 to 19.00 (last admission 18.50).

The real domes


Sketch of the domes by Franco Ravelli – Wikimedia Commons

The famous astronomer Roger Boscovich realized that the church was stable and that its pillars were suitable for supporting an astronomical observatory.

In 1787 the astronomical observatory was built on top of the church, with some very different domes from the one designed originally for the church.

Piazza dei Burrò

View of the square by Lalupa – Wikimedia Commons

In front of the church you will find Piazza St. Ignazio (also known as Piazza dei Burrò), surrounded by many 18th century buildings. But above all you will notice the existence of some buildings that present undulating shapes that recall the style of the French rococo writing desks.

These buildings  designed by Filippo Raguzzini around 1727, have a geometric scheme derived from the juxtaposition of three ovals. The architect’s goal was to amaze passers-by, highlighting the contrasts between the houses and the facade of the church. 

The Romans call them “burrò” from the term “bureaux” because during the Napoleonic invasion the French had their offices in this area.