Was Nero’s Domus Aurea as Big as the Ancient Sources Claim?



High vaulted ceilings of the Domus Aurea must have given a feeling of insignificance
to visitors.  Photographed by Mauro Orlando © 2015.


By Mary Harrsch
Ancient Times

I really enjoyed reading the article about the restoration of Nero’s Golden House, the Domus Aurea, in the September/October issue of Archaeology Magazine.  I especially appreciated the pictures as both times I have attempted to tour the Domus Aurea I have been thwarted.  In 2005, there was a sign at the entrance saying the site would open in the afternoon but when I went back to the entrance at the designated time, no one was around.  The second time I returned to Rome in 2009 I was told the Domus Aurea was deemed unsafe to visit and closed for repairs.

According to the article, the structure suffered extensive damage from vineyards that were planted atop Nero’s buried  palace in the 18th century.  A large public park was also built over the site in 1871 and enlarged by Benito Mussolini in the mid 20th century.  All of the plants and trees’ roots have broken the ancient mortar between the stones of Trajan’s baths sitting atop the palace and chemical compounds released by the roots have seeped down into underlying structures as well.

Just the sheer weight of all the plants is placing a strain on the palace’s structures even though the innovative flat arches and brick-faced concrete support structures are among some of the strongest of the ancient world.  The article mentioned a laurel tree that weighed over 30,000 pounds when it was removed and I remember standing by one about that size when I was there.

I was under the impression that most of the beautiful frescoes that inspired the artists of the Renaissance had crumbled from the walls but I see by the pictures in the article some are actually still intact!


Delicate floral patterns and mythological beings on a white background seen in frescoes of the Domus Aurea inspired decor throughout the Roman Empire including the Temple of Isis in Pompeii.  Photographed by Francois Spilliaert © 2011.

I think there are a lot of misimpressions about the Domus Aurea that architectural researchers hope to clear up once they have an opportunity to explore the remains more thoroughly.  The construction of the Domus Aurea is one of the key events leading to the downfall of the Roman emperor Nero.  The size of the structure alone was used to accuse Nero of causing the great fire of 64 CE so he could build a spacious new palace and “live like a human being”.  But was the structural portion of his original Domus Aurea really that big?

In his 1981 journal article “The Domus Aurea Reconsidered”, P. Gregory Warden points out that the Domus Aurea was essentially a landscape park in which the architectural components were subordinated to a greater landscape design.  Although earlier scholarship tried to estimate an overall size of 80 hectares of land, Warden suggests the complex covered a much smaller area about half that size.  He also points out that architectural remains in the Esquiline wing, essentially the only extant portion of the palace, indicate it is not even entirely Neronian.  He claims the eastern section is Flavian in date.

Furthermore, much of the Domus Aurea was actually rebuilt over Nero’s original palace, the Domus Transitoria as shown in the Archaeology article.  I originally read this in a book and was surprised since it appears to contradict claims that he cleared the center of Rome for his own use, contrary to ancient propaganda.  The expansive gardens, animal menagerie and artificial lake adjacent to the palace did consume quite a bit of property but they were open to the public sort of like Central Park in New York.

In his 1960 text, “The Golden House of Nero”, scholar Axel Boethius distinguished between peristyle and portico villas and described the Domus Aurea as the portico type.  Warden summarizes Boethius’ views:

“Lavish portico villas of the 1st century A.D., with spectacular views of the mountains or seacoast, are commonly shown in Campanian paintings.  They had also been built by emperors before Nero, although, of course, never in Rome.  Nero, however, did much more than import a landscape villa into the heart of Rome; the audacity of his design, or at least the design of his planners, Severus and Celer, was that he imported the landscape as well.  He took advantage of the devastations of the great fire of 64, combined new land with Imperial possessions, probably usurping some private holdings and public monuments as well, turned them all into a large park.  The entire complex, as Boethius noted, was much more than a villa, or architecturally perhaps much less; it was a landscape park in which the villa was but a component.  Buildings, perhaps more correctly termed “pavilions,” would have been scattered about, and the individual sections would have been linked conceptually rather than physically.” – P. Gergory Warden, The Domus Aurea Reconsidered

With this type of arrangement, determining the size of the actual Domus Aurea has proved challenging.  Warden says there has been too much reliance on a topographical study by C.C. Van Essen published in 1954.  Since that time, whenever a new structure was found within the area described by Van Essen as the Domus Aurea, structures have been accepted as such based on topography alone.

“However, if we examine these fragments of what is purported to be the Domus Aurea, we find a confusing diversity of construction techniques and architectural styles.” Warden says.

One such example is the nymphaeum found at the intersection of the Vile del Monte Oppio and the Via delle Terme di Traiano.  Although designated as part of the Domus Aurea, the nymphaeum is not aligned with the Domus Aurea and none of the brickwork appears to be Neronian.

“The nymphaeum is roofed with an elaborate system of groin vaults,” Warden explains, “In the entire Esquiline wing of the Domus Aurea there are only two groin vaults, considered the earliest existing examples of their kind, and they are found in the eastern part of the building, a section whose date, as we shall see, is problematical’.

I realize most of us are not architects, so, what is a groin vault?  In his excellent lecture, “Construction Revolution – Arches and Concrete”, part of the Great Courses series Understanding Greek and Roman Technology: From Catapult to the Pantheon, Professor Stephen Ressler of the U.S. Military Academy at West Point, explains that a groin vault is the shape formed when two barrel vaults intersect.  He then demonstrates how the Romans used concrete poured over a wooden frame to create a groin vault.  (Professor Ressler uses models throughout his course to demonstrate construction processes and I find them quite helpful to understand various Roman engineering techniques.)

Groin vaults were used extensively in the construction of Trajan’s Market particularly the aulus portion but were not characteristic of Neronian architecture or the western portion of the Domus Aurea.  Warden also notes that all three of the brickstamps found at the nymphaeum are Trajanic in date.

Warden contends that nothing north of the Esquiline wing can be safely attributed to the Golden House.  Apparently buildings to the east of the site of the artificial lake have been found to be from a later date as well.


Lavishly decorated vaulted ceiling in the Domus Aurea circa 1999.  Photographed by Jacqueline Poggi © 1999.

Warden admits there are many Neronian-era structures on the Palatine but thinks they should probably be attributed to the Domus Transitoria although a cryptoporticus linking them may have been built in conjunction with the Domus Aurea.

In 2009, Roman archaeologists excavating the Domus Aurea found remains of what they think may have been Nero’s famous rotating dining room on the Palatine Hill.

“The rotating dining room had a diameter of more than 50ft and rested upon a 13ft-wide pillar and four spherical mechanisms that rotated the structure.

The mechanism was a feat of Roman engineering, and moved thanks to the spheres beneath the wooden floor of the room, kept in constant movement by water being forced against them. Quite how this worked is still being researched.

Experts believe the dining room could be up to 60m long, but have so far uncovered several supporting pillars, one 4m in diameter, as well as a perimeter wall.

Archaeologist Maria Antonietta Tomei told how it was the circular shape of the building and the stone spheres that led the team to believe they had found the rotating dining room.”  – Nick Pisa and Claire Bates, Roman Emperor Nero’s legendary rotating dining room uncovered by archaeologists, The Daily Mail, September 30, 2009.

But, If you read Suetonius‘ biography of Nero, his distinction between structures within the Domus Transitoria and the subsequent Domus Aurea is a bit hazy.

“There was nothing more ruinously wasteful however than his project to build a palace extending from the Palatine to the Esquiline, which he first called ‘The Passageway’, but after it had burned down shortly after completion and been re-built, ‘The Golden House’. The following details will give a good idea of its size and splendour…Inside there was gold everywhere, with gems and mother-of-pearl. There were dining rooms whose ceilings were of fretted ivory, with rotating panels that could rain down flowers, and concealed sprinklers to shower the guests with perfume. The main banqueting hall was circular with a revolving dome, rotating day and night to mirror the heavens.” – Suetonius, The Twelve Caesars, Nero, Book Six: XXXI

Furthermore, Warden says literary sources point to Neronian builders focusing their efforts on areas other than the Palatine.

“There are also undoubtedly remains of Neronian structures to the south, on the edges of the Caelian in the area of the Temple of the Deified Claudius,” Warden writes, “These Neronian works …are considered to have been more like facades and porticoes with elaborate hydraulic works than buildings proper.”

So, according to Warden, an analysis of the topology would indicate the Domus Aurea was centered on the artificial lake and hugged the slopes of the surrounding hills where structures there were hardly more than theatrical facades for elaborate landscape effects.


View of the Colosseum, once Nero’s artificial lake, from the Domus Aurea.  Photographed by Jean-Pierre Dalbera © 2011

Then Warden tackles issues with differences in construction and the chronology of extant remains.

He points out that the most obvious differences in the remains on the Esquiline are the fact that the western section of the complex is primarily rectilinear with a porticoed southern facade and relatively traditional while the eastern half of the complex is structurally complex with its octagonal room with flat arches and a domed concrete ceiling with oculus, groin-vaulted subsidiary rooms and an apsed nymphaeum.


Innovative flat arches and concrete domed ceiling with oculus of the spacious
octagonal reception room of the Domus Aurea.  Photographed by Jacqueline Poggi © 1999.

The two sections are also fused awkwardly and there is a distinctive difference in mortar color from one section to the next.

“Some of the brickwork of the Esquiline wing is very similar to brickwork in the Colosseum,” Warden observes. “…at least some of the brickwork of the Esquiline wing is probably Flavian in date.  The crucial question is whether the later brickwork represents minor alterations or an entire building phase.”

The degree of decoration may also point to later construction in the eastern section.

“…the concrete dome of the octagonal room still shows signs of the planks of the wooden armature onto which it was cast.  Further, there is no evidence that the concrete of the dome was ever stuccoed or revetted.  While this eastern section may never have been finished, the western section was not only completed but also fully decorated, and it was also extensively restored in later, probably Flavian times.”

Although Nero dedicated the Domus Aurea before his death, it, like many buildings in antiquity that were dedicated before completion, may not, in fact, have been completed.  Suetonius, in his biography of Otho, mentions that Otho put aside 50 million sesterces for the completion of the Domus Aurea.  This would indicate that it was not finished at the time of Nero’s death.


Detail of a fresco in the Domus Aurea.  Photographed by Francois Spilliaert © 2011.

Cassius Dio recounted that Galeria, the wife of Vitellius, found the place too gloomy for her taste and that Vespasian preferred the Horti Sallustiani instead.    Pliny the Elder notes that the famous sculpture of the Laocoon, reported found in either the Termae Traiani or the Domus Aurea, resided in the palace of Titus.  Since this structure has never been identified, some scholars think the eastern part of the Domus Aurea may have been identified as the Domus Titi.


The Trojan Priest Laocoon and his sons attacked by sea snakes because Laocoon had tried to warn
the Trojan citizens of the danger of bringing in the wooden horse.  This sculptural group was found
“in the palace of Titus” in the general area of the Domus Aurea in 1506.  Photographed by
Mary Harrsch at St. Peter’s Basilica in Vatican City © 2005

Warden points to one more literary source indicating a portion of the Domus Aurea was, in fact, Flavian.

“The complex spatial planning of the eastern half would accord well with our view of Flavian architecture, and in support of a Flavian date there is one more piece of evidence. Eusebius, writing at the beginning of the 4th century A.D., mentions in a long list of Flavian monuments a certain Mica Aurea, the remains of which have not been identified. It has been suggested by A.M. Colini, on the basis of the name, that the Mica Aurea could have been a pavilion or a section of the Domus Aurea which was restored under Domitian.”

As an architectural historian, Warden raises the question that if the eastern section of the Esquiline wing of the Domus Aurea is not the work of Nero’s famous architects, Severus and Celer, but is instead the work of Domitian’s architect, Rabirius, historians should perhaps not view the original Domus Aurea as the revolutionary structure marking the turning point of Roman architectural engineering when concrete replaced opus quadratum as the material of choice “to express newer and freer definitions of interior space”.

As a student of Roman politics, I think this entire discussion makes me wonder if most of the hype around Nero’s lavish lifestyle was just one more example of imperial Roman propaganda used to villify yet another deposed emperor!


Warden, P. (1981). The Domus Aurea Reconsidered. Journal of the Society of Architectural Historians, 40(4), 271-278. Retrieved September 7, 2015, from http://www.jstor.org/stable/989644