On via Ostiense, a few stops from the Pyramid, there is an industrial building of brick and glass that looks nothing like a museum. Inside, in front of two black diesel engines as tall as a house, hundreds of Roman statues in white marble stand in rows.
The contrast is not a curatorial gimmick. The Centrale Montemartini was a real power station, and the machines have stayed where they worked: the statues arrived later, and what lights them is the daylight coming through the industrial windows. No neutral backdrop, no display case, no gallery half-light. Here a Hellenistic Muse and a crankshaft weighing eighty-one tonnes share the same room, and you realise that both were built to last.
The route that follows keeps the order of the two main halls, from the Machine Room to the Boiler Room, and ends in a space where there is no marble at all, but a train.
How did a collection of imperial marbles end up inside a power station?
Let’s begin!
A power station, and how the statues got here
The plant was inaugurated on 30 June 1912 by mayor Ernesto Nathan, and it was the first public electricity plant in Rome. The name is that of Giovanni Montemartini, the socialist councillor who had been the theorist of municipal utilities. He died in July 1913, during a session of the city council, and the plant was named after him. It worked for over fifty years and was shut down in 1968.
Then it stood empty, until in 1997 the Capitoline Museums had to clear some rooms for restoration work and looked for temporary shelter for the sculptures. What came out of it was an exhibition whose title announced the experiment, Le macchine e gli dei, the machines and the gods. It was meant to last a couple of seasons. It became the second site of the Capitoline Museums.
As you walk, keep one thing in mind, because it explains almost every label you will read. Most of these pieces do not come from scientific excavations. They come from the building works of the late nineteenth century, when Rome became the capital and whole districts went up on top of the imperial villas, and then from the construction sites of the 1930s: these are works that came out of the ground along with the foundations of apartment blocks.
1. The two diesel engines in the Machine Room
Start with the engines, because they demand your attention first and because the museum treats them exactly as it treats the marbles.
They are two two-stroke diesels built by Franco Tosi of Legnano, put into service on 21 April 1933 in the presence of Mussolini, with a combined output of fifteen thousand horsepower. The crankshaft comes in three pieces, weighs eighty-one tonnes and is more than twenty metres long. Go up to the side walkways: the little stairs, the handrails and the brass plates are still the ones used by the workers who did their shifts in here.
Then lower your eyes to the statues lined up in front of them. It is the same operation an archaeological museum performs on a capital: keeping a technical object that is no longer of any use, because it tells you how the people before you worked.
2. The pediment of the Temple of Apollo Sosianus
In the Machine Room, on a stepped podium that reconstructs the original triangular arrangement, you find the sculptures of the pediment of the Temple of Apollo Sosianus, the temple of which three columns still stand beside the Theatre of Marcellus.
The scene is an Amazonomachy, the battle between Greeks and Amazons, with Heracles and Theseus fighting under the eyes of Athena and Nike. Look for the bodies bent backwards in the low corners of the triangle: the composition had to fill a space that drops away at the sides, and the figures were designed for that geometry.
Why are these sculptures not Roman copies, like almost everything else here?
Because they are not Roman at all. They are Greek originals of Attic workmanship, carved between 450 and 425 BC, and they come from the temple of Apollo Daphnephoros at Eretria, on Euboea. They were brought to Rome by Gaius Sosius, who rebuilt the temple after his triumph of 34 BC: war booty remounted on a new building, four centuries after being carved. Next time you walk past the columns beside the Theatre of Marcellus, you will know what stood on top.
3. The portrait called Cleopatra
It is a marble head thirty-nine and a half centimetres high, Hellenistic in date, and one of the smallest and most photographed pieces in the museum. The label presents it as a portrait of Cleopatra.
The detail worth taking away is not the name, it is the line underneath: it was found in Rome in via Labicana, in 1886. From the same street, in 1910, came the Augustus of via Labicana, the portrait of the emperor with his head veiled that is now one of the works at Palazzo Massimo alle Terme. Two portraits a few hundred metres apart, two different museums, the same season of digging.
4. The Muse Polyhymnia
In the Boiler Room, in the section devoted to the Horti Spei Veteris, stands the statue that ends up on the museum’s posters more often than any other: the Muse Polyhymnia, marble, one hundred and fifty-nine centimetres high, a copy of a Hellenistic original.
She is wrapped in her mantle up to the chin, leaning her elbow on a support, her left fist showing through the cloth and her head turned aside, her gaze somewhere beyond whoever is looking at her. She was found in via Terni in 1928, in the Porta Maggiore area where the imperial horti once spread out: gardens that were residences, with pavilions, fountains and sculptures arranged like a private museum.
Look at her from three paces back and then from close up. From a distance she is a compact figure, almost a block; from close up the mantle is carved with folds that change direction on every plane, and that is where you see the hand of a copyist who knew his trade.
5. The Seated Girl
A little further on, in the Horti Liciniani section, a girl sits in Pentelic marble, a Hadrianic creation in Hellenistic taste. She is one of the sculptures the museum shows without glass, at exactly the height at which you can look her in the eye.
She comes from the so-called Temple of Minerva Medica, and here is the thing almost nobody knows: that temple is not a temple. It is a great ten-sided hall of the fourth century, a reception pavilion inside a residence with gardens, and the name has stuck to it from a mistaken attribution made centuries ago. Which gardens it belonged to, incidentally, is still debated. You can see it from the window, its dome collapsed and its brickwork bare, as your train pulls into Termini: a ruin in the middle of the tracks.
6. The mosaic with hunting scenes
Also from the Horti Liciniani, the imperial residence of Licinius Gallienus, comes the largest piece in the Boiler Room: a polychrome mosaic with hunting scenes from the early fourth century, measuring fifteen metres by nine.
Do the arithmetic: that is a hundred and thirty-five square metres of floor, the area of a large flat. It was not a picture for a wall, it was the surface people walked on, and the luxury lay precisely in that, in treading on a hunting scene assembled tessera by tessera.
It was found in 1904, near the church of Santa Bibiana, a short walk from Termini station: another piece of imperial Rome that resurfaced under a building still in use.
7. The train of Pius IX
The last room has no marble. It has three railway carriages from 1858, given to Pope Pius IX by the companies that were building the papal railways and manufactured in France.
One is the loggia of blessings: an open carriage with a balustrade, from which the pope could bless the crowd as the train slowed down in the stations. Another is a chapel. The third is a throne room for audiences.
What is a papal train doing inside an archaeological museum?
It tells the same piece of history as the statues you have just seen, from the opposite side. On 3 July 1859 Pius IX made his first journey in these carriages, from Porta Maggiore to the station at Cecchina, towards Albano. Eleven years later the Papal State no longer existed, Rome was becoming the capital of the Kingdom of Italy, and the excavation works began that would bring most of the marbles in this museum back to the light. The train and the statues share the same building because the same date put them together.
Practical information
Details checked on 16 September 2026 on the official Centrale Montemartini website. Prices and opening hours change: check again before you travel.
Tickets. Full price is 11 euros and covers the permanent display; the reduced ticket costs 6.50 euros and is 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 is free for anyone resident in Rome and the Metropolitan City, on showing an identity card at the desk: if you are coming from elsewhere, you pay. Children under six, people with disabilities with a companion and MIC card holders also go in free. On the first Sunday of every month admission is free for everybody. A discount almost nobody uses. Every Wednesday, in the last two hours of opening, non-residents pay the reduced rate, 50 per cent off. Opening hours. Tuesday to Sunday 9:00-19:00. Closed on Mondays, on 1 May and on 25 December. Last admission is one hour before closing. Getting there. The museum is at via Ostiense 106. The nearest stop is Garbatella, on metro line B, a few minutes away on foot. Alternatively get off at Piramide and walk along via Ostiense. How long to allow. The seven works in this guide and the two main halls take an hour and a half. Allow two hours if you stop on the walkways around the engines and in the train room.
Where to go from here
If you liked this place, its larger twin is a kilometre and a half from the Capitol: the Capitoline Museums, where most of what you have just seen comes from. The most useful comparison, though, is with the city’s other great store of imperial marbles, the Museo Nazionale Romano, which I have covered through the works at Palazzo Massimo alle Terme and at Palazzo Altemps.
If you are still deciding where to start, the reasoned list with the closing days is in Museums in Rome: the 8 you should not miss.
Photo credits: machine room by Alephoto (CC BY-SA 4.0); pediment of Apollo Sosianus and hunting mosaic by Lalupa (CC BY-SA 3.0); Muse Polyhymnia by Carole Raddato (CC BY-SA 2.0); train of Pius IX by Carlomorino (CC BY-SA 4.0), all from Wikimedia Commons.
