On the Tiber embankment, inside a case of glass and white travertine, stands a block of marble as tall as a room, covered in figures on every side. Inside, up a few steps, there is an altar.
That is the Ara Pacis Augustae, the Roman monument that is hardest to look at properly: almost everybody walks through it in ten minutes convinced it is a sculpture. It is not. It is a text, and each side says something precise: the figures are not decoration, they are a list of people, some of them identifiable by name.
The six reliefs in this guide are the six chapters of that text, in the order in which it makes sense to read them, and at the end you will find the story of how this altar was put back on its feet twice within a century.
How do you read a monument that was designed to be read?
Let’s begin!
The altar, and where it actually stood
On 4 July 13 BC the Senate decreed the building of an altar to Peace for the return of Augustus from his campaigns in Spain and Gaul. The consecration came on 30 January 9 BC, which was also the birthday of Livia, the emperor’s wife.
The altar did not stand here. It rose in the Campus Martius, one Roman mile from the pomerium, the sacred boundary beyond which commanders laid down their military powers on their return. It was not just any spot: the peace the monument speaks of is the peace that follows a general coming home.
The monument you see today is a few hundred metres from the original point, on the embankment: it was brought here in the twentieth century, and the story of that move is at the end.
1. The procession on the south side
Start with the long side, the one towards the river, and it is the part that gives meaning to everything else.
There is a procession of real people moving to the right: priests, lictors, magistrates and the imperial family. They are not ideal types, they are portraits, and the relief is organised according to the order of precedence of those years, around 10-9 BC.
What sets this procession apart from a line of important people?
The children. There are children inside the official procession, clinging to the adults’ clothes, one turning round, one pulling at the cloak of the person in front. No Greek public monument would have put children inside a state ceremony. They are here because the message is not only «there is peace»: it is there is a dynasty, and these are the heirs. Look at the heads of the adults turning towards them, and compare the rhythm with the Parthenon frieze, which the project openly looks to.
2. The procession on the north side
The opposite flank carries the other half of the same procession, with more priests, magistrates and members of the family.
It is the part with the most modern integrations: many heads were remade when the fragments were put back together. Go closer and look for the differences in the surface: ancient marble has a patina and a grain the completions do not have, and once your eye has taken the measure, you can tell for yourself what is original.
3. Aeneas sacrificing, and the doubt about his name
Move to the west side, the entrance side, and look at the right-hand panel. A mature man, his head veiled, performs a sacrifice in front of a small temple: the traditional reading is that this is Aeneas, newly arrived in Latium, sacrificing to the Penates.
The point of the panel is genealogical. Augustus’s family, the gens Iulia, traced its origin back to Iulus, son of Aeneas: putting Aeneas on the Altar of Peace means saying that the emperor descends from the founder, and that the peace is the fulfilment of a story that began a thousand years earlier.
Over the last few decades, however, part of the scholarly world has proposed recognising in that figure Numa Pompilius, the priest king who closed the doors of the temple of Janus, and the reading has gained ground. The veiled head and the gesture of sacrifice fit both, so the scene does not settle it: it does change the meaning of the panel, though, and it is worth knowing while you look at it.
4. The Lupercal
On the other side of the entrance, to the left, the panel is reduced to fragments, and it takes patience to reassemble it with your eyes: it is the Lupercal, with Mars looking on at the scene of the she-wolf and the twins Romulus and Remus.
Hold it together with the Aeneas panel, because the two answer one another. On the right the Trojan descent, on the left the founding of Rome; on the right religious piety, on the left the warlike origin. Whoever entered the altar passed between these two ideas, and that was intended.
5. The Tellus, the panel everybody photographs
On the east side, above, is the most reproduced relief of the monument. At the centre a female figure sits with two children in her lap, among fruit and ears of corn, and at her feet are a cow lying down and a sheep. At the sides, two female figures with their veils billowing above their heads: one on a sea monster, the other on a great bird.
She is called Saturnia Tellus, the Earth, and there has been long debate over whether she is the Earth, Italy, Peace or Venus. The meaning, in any case, is the prosperity that peace produces: animals at rest, water running, harvests.
On the same side there was the panel with the personification of Roma in arms, now largely lost: only minimal fragments survive, and what you see is for the most part a reconstruction.
6. The acanthus scrolls, and the twenty swans
Now lower your eyes. The whole lower register of the enclosure, half the surface of the monument, is taken up by a vegetal frieze. From the acanthus clumps spring scrolls that wind into symmetrical spirals; out of those grow vine, laurel and ivy leaves, and flowers of different kinds.
It is the part almost everybody walks past without stopping, and it is the most surprising, because it is inhabited. Hidden among the leaves are twenty swans with their wings spread, marking the rhythm of the composition, and then lizards, frogs, snakes inside a nest, snails, butterflies, scorpions.
Why put such minute wildlife on a state monument?
Because it says the same thing as the fruits of the Tellus, but at the scale of small things: where there is peace, nature gets on with its work. Look for the snake approaching the nest: it is one of the very few moments of tension in the whole decoration, and it did not end up there by chance.
Finally climb the steps and go inside the enclosure. The inner walls imitate a wooden fence with garlands hung between ox skulls, that is, the temporary form of a field altar translated into marble. On the altar itself runs the frieze of the annual sacrifice, with the Vestals and the pontifex maximus on the inside and, on the outside, the camilli and the animals led to the sacrifice.
1938, 2006, and the two reconstructions
We have this monument because it was put back together piece by piece, and the story runs over four centuries.
The first fragments came out in 1568 under Palazzo Peretti, in via in Lucina. More arrived between 1859 and 1879, and it was the German archaeologist Friedrich von Duhn who worked out that they all belonged to the altar of Augustus. The decisive excavation is that of 1937-1938, and to carry it out under an inhabited building the ground was frozen to keep it solid: a highly advanced technique for the time.
On 23 September 1938, the birthday of Augustus, the reassembled monument was inaugurated in a pavilion built by Vittorio Ballio Morpurgo next to the Mausoleum. It was an openly political operation, during the Augustan bimillenary staged by the fascist regime.
The present case is by the American architect Richard Meier: work began in 2000 and the museum was inaugurated on 21 April 2006, the birthday of Rome, by mayor Walter Veltroni. It was the first contemporary building erected in the historic centre of Rome since the fall of fascism, and the controversy was violent. In 2004 the critic Vittorio Sgarbi set fire to a model of the project in piazza Augusto Imperatore; on the eve of the opening he declared he would like to blow it up, and called it «a Texas gas station».
Make up your own mind by looking at two things: the light, because the case is designed to light the reliefs with the daylight off the river, and the relationship with the square, which is the part on which the argument has never closed.
Practical information
Details checked on 16 September 2026 on the official Museo dell’Ara Pacis website. Prices and opening hours change: check again before you travel.
Tickets. Full price is 11 euros, the reduced ticket 6.50 euros, for non-residents between 6 and 25, holders of an annual ATAC pass and groups of at least twenty. Free admission. Since February 2026 admission to the museum is free for anyone resident in Rome and the Metropolitan City, on showing an identity card; excluded from the free entry are the temporary exhibition space and the multimedia show L’Ara si rivela, which have their own ticket. Children under six and people with disabilities with a companion also go in free, and the first Sunday of the month is free for everybody. Opening hours. The museum opens every day, 9:30-19:30, and closes only on 1 May and 25 December. On 24 and 31 December the hours are 9:30-14:00. Last admission is one hour before closing. The right day. It is one of the very few museums in Rome with no weekly closing day: if you have a Monday to spare and everything else is shut, this is open. Getting there. The entrance is on lungotevere in Augusta, at the corner with via Tomacelli. The nearest metro A stations are Spagna and Flaminio, both about ten minutes away on foot; from piazza del Popolo you walk down via di Ripetta. How long to allow. The six reliefs in this guide and a full circuit of the enclosure need an hour. Allow half an hour more if you add the multimedia show.
Where to go from here
The altar is a few steps from the Mausoleum of Augustus, the monument this part of the Campus Martius was laid out for. To see the portraits of the same people you recognise in the procession, the right place is Palazzo Massimo alle Terme, where the Augustus of via Labicana is.
That family governed from the Roman Forum and the Palatine, and Trajan’s Markets, with the Museum of the Imperial Fora, put back together the pieces of the squares that surrounded them.
Photo credits: enclosure of the Ara Pacis by Joel Bellviure (CC BY-SA 4.0); south side procession and altar frieze by Luciano Tronati (CC BY-SA 4.0); Saturnia Tellus by Chris Nas (CC BY-SA 4.0), all from Wikimedia Commons.
