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~ D.I.Y. Rome ~
an online guide, with maps and suggested routes


INTRODUCTION

Rome is the city in the world with the longest set of ancient walls still partly standing.
This unique relic of roman history, though, is somewhat neglected by the thousands of tourist who visit the city every day: very few of them pay attention to these massive structures, as their interest is mainly caught by famous buildings and sites such as the Roman Forum, the Pantheon, or the Colosseum.
Certainly less beautiful than these gems, the walls proved more useful to the city than any other well-known monument or building. And still today they stand as an important memory of the city's ancient boundaries.

The several restoration works carried out through the ages, in order to keep them strong and steady, give reason for the good state of preservation of the set of walls built in the 3rd century AD: unlike other ancient buildings, they mantained their original function until the end of the 1800s. Many of the original gates are still in place, as well, and some of them have witnessed important historical facts.
Besides their importance during wartime, the city walls enabled the local authorities to keep under control the many people who every day entered or left Rome, as the only way in or out was through the gates: the doors were usually kept under sentry during daylight, and closed after dusk. And since a tax was usually imposed on people and on goods entering the city, the gates yielded also a considerable income for the municipality.

stretch of Aurelian's Wall by St.John's Gate →

Much more than weapons, the worst enemies of Rome's ancient walls are invisible: water infiltration, weed roots, and in modern times air pollution too, represent a constant menace that seriously jeopardizes the steadiness of these massive giants, causing them to crumble. The collapse of a whole stretch of Aurelian's wall on the southern side (now fully restored), occurred only a few years ago, acted as a serious alert.
The city's authorities are presently keeping under control the structural stability of a sample stretch of wall, with the aid of teams of experts, in order to tune up new diagnostic techniques which in the future should allow a permanent monitoring of the whole set of walls.

Rome's walls are not walkable like the medieval ones found in many other European cities, except a short stretch on the southern side. This is partly due to the same structure of the wall, and partly for security reasons. Nevertheless, it is possible to follow the main set of walls all round its original perimeter: this long, interesting and rather unusual tour takes the visitor through many districts, some of which off the city's commonly visited areas. A few remains, not far from the main walls and gates, can also be reached by making short diversions from the main route; for those who feel like adding a little extra distance to the long walk, they make an interesting integration of the main tour.

The main aim of the following pages is an invitation to visit these walls, either virtually or actually.
I have tried to keep in mind both the many visitors who will take the more comfortable tour, sitting in front of their PC monitors, but also those who are planning to visit Rome (or will hopefully do so, after browsing these pages): the guide has plenty of pictures, a full description of the tour, detailed maps with a suggested route (stored in separate files, so to avoid bulky pages), and it can be easily printed, to be used as a handy reference while walking around the walls.


scroll down the historical notes to access the different sets of walls
in the following sections the yellow buttons take back
to previous pages, the blue ones bring out maps

leads to the opening index
of the relevant section		 brings out a map of the
ancient walls and main roads
leads back to this page
(historical notes and walls index)		 brings out a large map of the
area with suggested routes

HISTORICAL NOTES
AND
WALLS INDEX

Since its foundation, Rome has always adopted defensive means, to prevent the several populations surrounding the original nucleus from invading the city.
They are not one single structure, but several walls belonging to many periods. They were built with different techniques, according to the different weapons they had to face, from early enemies' stones, to catapults, to more powerful cannon balls.
Each of them will be therefore dealt with separately, as individual structures.
All of them are conventionally named after the ruler (king, emperor or pope) who had them built.
For a large map of their complicated perimeters and ancient roads that ran by the gates, select the clickable image above.
 click on the picture for an enlargement
large map of the walls and main ancient roads


ROMULUS' WALLS

We know little about the very first defensive structures that protected Rome's original nucleus, over 2700 years ago; the top of two adjoining hills, the Capitolium and the Palatine, was enclosed by two separate walls; the one on the Palatine was probably rebuilt over a pre-roman structure, and protected Romulus's House, claimed to be the dwelling site of the mythical founder and first king of Rome.
Only few visible traces, both of the Palatine's and of the Capitolium's wall, now survive (the latter is shown on the left). Therefore, these are the only walls not dealt with by the following pages.



SERVIAN WALLS
(or REPUBLICAN WALLS)


They are named after Rome's sixth king Servius Tullius: by tradition, he was the first ruler to order the construction of an early defensive structure around the city. Also in this case it is impossible to state a precise date. According to reliable sources, by the 6th century BC the city of Rome could indeed rely on some sort of protection; nevertheless, there is enough proof that an actual wall was not built until the late 4th century BC, during Rome's republic, whence the alternative name. In particular, Livy (i.e. Titus Livius) mentions that shortly after Rome's devastation by the Gauls, in 390 BC, new taxes were levied for the making of a wall of stone blocks (Ab Urbe Condita, book VI).
A further extension, beyond the left banks of the river Tiber up to the top of the Janiculum hill, was built two centuries later.
Therefore, the evolution of this set of walls was probably rather complicated.

The earlier defensive technique probably consisted of a sort of mound dug in the ground; the earth coming from the latter was simply used to make a long heap on the inside, as a further protection.
Later in time, a real set of walls took the place of this primitive boundary. But along the north-eastern part of its course, a deep mound was still found outside the wall, as a part of a structure called agger (from the Latin ad gerere, "to bring, move towards"): the earth and stones dug from the mound were piled on the inner side of the boundary, between the wall itself and a counterscarp (i.e. a lower wall that prevented its downslide).

Either belonging to the agger or standing alone, the wall was built according to the dry-stone technique, i.e. without any mortar; large square blocks (opus quadratum) were piled one on top of the other, in multiple rows. The blocks are made of tufa, a porous rock consisting of consolidated volcanic ashes, commonly used as building material since ancient times (in Rome tufa was used for the making of buildings up to the early 1930s!).

Unfortunately, no more than a few fragments of these walls are now left standing, scattered in various parts of the city, sometimes in strange places where it would be difficult even to figure that once by that spot ran a defensive wall.
Their full perimeter could be defined, more or less precisely, thanks to data based on historical sources and archaeological excavations.
frieze from the Basilica Aemilia
fragment of frieze from the Basilica Aemilia (179 BC)
that features two workmen building the wall


detail of the variety of tufa known as cappellaccio;
its several whitish inclusions are of volcanic origin

By the end of the 4th century BC, the city boundaries enclosed the famous seven hills, or Septimontium, over which the city was originally built: the Capitolium and the Palatine (i.e. the early nucleus), the Aventine, the Esquiline, the Quirinal, the Viminal and the Coelian.
Very soon, though, the city began to expand rapidly, especially from the late 1st century BC, during the imperial age.


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THE SERVIAN WALLS
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AURELIAN'S WALLS

By the 3rd century AD Rome had expanded so much beyond its old boundaries that the Servian walls had become useless. Therefore emperor Aurelian, who had reunited the crumbling empire and quelled internal revolts, decided that time had come to build a further set of walls, and to do so as soon as possible: in only five years (from 271 to 275) Rome's new boundaries enclosed a much wider area, especially on the western side of the city. Nevertheless, Aurelian did not live long enough to see the work finished, as he died a few months before it was completed.
The new defensive system was built with bricks. Unlike the previous set of walls, these ones had square towers at regular distances, and a walkable passage on the inner side that the soldiers used for moving along its length, remaining fully protected (see the opening picture and the one below).


detail of the walkable passage on the inner side
These are the walls still standing for most of their length, with the only exception of the western stretch built over the Janiculum hill, replaced by the popes' walls during the first alf of the 1600s. During the centuries, restoration works were carried out many times, what can be told by the different brick and stone textures, by some inscribed plaques and by several different coats of arms of the popes who had the works carried out.
Also most of the gates, albeit standing on their original sites, have gone through changes; some of them has been walled up, some others have been refurbished according to new functional needs. But they all maintain their fascinating allure.


The works for the making of Aurelian's wall carried on so hastily that when their scheduled direction ran across large buildings, no change was made to the project, nor any demolition was carried out, but the manufact was literally crossed, incorporating it in the defensive structure!

Since the walls had to be ready in a very short time, when civil or military pre-existing buildings happened to be along their way, Aurelian's architects did not dismantle them, nor did they change their planned direction: they simply crossed the older building!

Despite their hasty making, these walls proved far more steady than any ancient architect could have ever imagined: after seventeen troubled centuries, catapults, battering rams, cannons, bombs and even earthquakes have not been strong enough to take them down. Nevertheless, from time to time the wall was subject to damages caused by enemies or simply due to the structure's ageing, which required restoration works.

In ancient Roman times, both the walls and the gates were built according to criteria essentially inspired by practical purposes: defensive systems showed no trace of decorations nor embellishments. The gates were simple archways, not very tall, while the walls, which lacked a crenellation, were marked by towers with a square section, set at regular distances.
Porta Asinaria features the typical alterations by Honorius

By the turn of the 5th century, the young emperor Honorius, fearing an impending attack by the barbarian populations, had the extant gates altered by facing them, either partly or in full, with a thick white stone layer that covered the brick texture, making it more resistant to enemy assaults.
Stout semicircular towers were built, encasing the gate whose top part now had a crenellation, sometimes extended to the towers and to the nearby walls. The gates with two archways (namely, Porta Praenestina, Porta Appia, Porta Portuensis) had one of them blinded, for the sake of an easier defense. Other constant features typical of Honorius' changes were the presence of a portcullis, less easy to break down, operated from a chamber located above the archway, that was given light by a series of small windows.
Furthermore, the facing often bore Christian symbols or other decorations (such as the curious 'lumps' in the picture on the left), always for apotropaic purposes, almost as if, besides the mechanical device, in this way the gates may have increased their defensive potential also 'spiritually'.
But Honorius' efforts were not enough to prevent Rome's fall to Alaric I, king of the Visigoths, only about ten years later, in 410.
detail of the stone layer: note the portcullis rail
and the small Latin cross on the keystone of the arch
Also in 537-538 the walls witnessed another siege of the city, which in the meantime had been taken by the Bizantynes, this time by the Ostrogoths led by general Vitiges; this gave historian Procopius of Caesarea the opportunity of leaving a detailed description of the clash, which also contains some interesting information concerning the wall's structure by that time.

During the Middle Ages, the walls and the gates remained the original ones, except for a few rough restoration and reinforcement works.
Only in the second half of the 1500 two new gates were built (namely, Porta Pia and Porta San Giovanni), designed according to a Renaissance fashion, while a third one of similar shape (Porta del Popolo) replaced the originale Roman one. And about fifty years later also Porta Portuensis and Porta San Pancrazio were replaced during the making of the walls sponsored by pope Urban VIII.

Interestingly, Aurelian's walls kept acting as a boundary of the urban area, besides being also its main means of defense, up to 1870, when Rome was set under siege for the last time by the Italian army of king Victor Emmanuel II, who got the better of the Papal State.
In recent times, as of the turn of the 1900, several new archways had to be opened through the ancient wall, in order to build new streets that cross the old boundary and enable the traffic to flow smoothly through the gates already extant.


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AURELIAN'S WALLS
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THE POMERIUM

As far as now the physical walls have been described, i.e. the ones made of stones or bricks that kept the enemies away from the city. Besides this material boundary, Rome also had a formal boundary, called pomerium (a contraction of post = "beyond" and moerium = archaic term for "wall"). It marked an inner territory, which was considered sacred, and therefore had some important religious and legal implications.
Its perimeter was marked by marble cippi such as the one in the pictures, set at a regular distance. Only eight of the original cippi have been retrieved so far, whence today's difficulty in tracing such boundary. Furthermore, the pomerium was not perfectly parallel to the walls, so that the strip of land between the latter and the sacred boundary had an irregular extension. This was partly due to the fact that when new walls were built, the pomerium was left as it was, only to be enlarged on different occasions.
As a matter of fact, the pomerium was considered the real boundary of the city: whatever fell within its line was the actual Rome, whereas the land between the cippi and the walls was simply 'Rome's property'.

The Romans inherited the use of a religious boundary from the Etruscans, so very likely a pomerium existed since the very foundation of the city: this was the mythical line traced by Romulus, the first king and founder of Rome. The furrow left by his plough symbolized a moat. Servius Tullius, the sixth king, lengthened its course, likely by the time when a first defensive structure was built around the city. Instead it was not modified when an actual set of walls was built (4th century BC). Under the dictatorship of Sulla (82-80 BC) the pomerium was lengthened again, and then other times during the imperial period, by a number of emperors, among which Octavianus Augustus, Claudius (right), Vespasian (above), Trajan, Aurelian.
The most important spots, such as the temple of Jupiter, the Fora, the Curia where the senators met, and others were inside the boundary; the Campus Martius, where the soldiers trained, the temple of Isis, the Theatre of Marcellus, and other and was outside. Also the whole Aventine hill was left outside the original pomerium, and so did the Esquiline hill.
Nobody could cross the pomerium carrying weapons, not even generals (only in times when a dictator was appointed, he was entitled to infringe this rule). Crossing the boundary was also forbidden for monarchs of other cities or states who, when paying an official visit to Rome, had to stop before its ideal line. Nobody could be buried inside the pomerium, giving reason why even the imperial mausoleums were located on relatively outer spots.



THE POPES' WALLS

Defensive structures began to rise around the Vatican no sooner than in the 6th century. Until then, this area was rather vulnerable, as it was not surrounded by walls, nor the hight of the Vatican Hill could represent a real natural boundary. But nothing really worth attacking the Vatican could be found there, until emperor Constantine decreed freedom of religion for the Christian believers, and had a large basilica built on the spot of the saint's burial.
Pilgrims from many countries started visiting St.Peter's tomb; during the medieval times, they became a real multitude. The basilica, its ornaments, its treasury, gradually became a more sensible target during enemy raids.
The first wall ever built in this part of town dates back to the time when Rome fell to the Ostrogoth king Totila (546-550). He built a wall in the area that runs from St.Peter's to the Hadrianaeum, i.e. emperor Hadrian's tomb, which was being turned into a fortress.
In the 9th century, pope Leo IV had a longer wall built; it curled around St.Peter's basilica, and incorporated the remains of the one by Totila, that had fallen several times.
The importance of this wall consisted in the fact of enclosing the whole Vatican Hill, thus turning the open area into a citadel, which became known as Leo's City; this was though not considered an official part of Rome until pope Sixtus V annexed it to the urban districts in 1585, thus becoming the city's fourteenth historical district.
Leo IV's wall had already been standing for 500 years, when in the 15th century pope Nicholas V had to carry out major restorations, and on this occasion he added some huge round towers, most of which can still be seen today.

A few years after the German mercenaries of emperor Charles V had savagely sacked Rome (1527), pope Paul III (1534-49) strengthened the citadel's defense by having big bastions strategically built by the northernmost and southernmost corners of Leo's City, which by that time had already grown beyond the old boundaries.
These bastions, though, were not linked by a wall. This only happened a few years later, when pope Pius IV (1559-65) decided to have a new full boundary for the Vatican and the citadel, running from Sant'Angelo Castle (former Hadrian's tomb) all the way round the Vatican, down to the banks of the Tiber.
Also these new walls were made of bricks but, unlike the previous ones, their outer side was shaped as a steep slope, with a white kerbstone or rim made of travertine (picture on the right) that follows the whole length of the perimeter. Arrow-shaped bastions, in place of old towers and embattlements, housed placements from which modern weapons such as cannons could be used.
Curiously, today this set of walls still keeps its original purpose, marking the official boundary between the Vatican State and the Italian Republic.

A long extension was then built by Urban VIII (1623-44) about one century later, along the Janiculum Hill. Since the old wall by Aurelian was no longer in good condition, the pope decided to enclose the top of the hill within Rome, thus expanding the city towards the western side of the Janiculum, and slightly shortening the ancient roman boundary by the southernmost end of the wall.

Rome's ancient boundaries compared to the modern city
Thanks to this last addition, as of the 17h century the city was surrounded once again by a full set of walls, from Porta Flaminia (now Porta del Popolo) to Sant'Angelo Castle: from here, the small unprotected area could be easily kept under control by the castle's artillery.

Clicking on the button on the left brings out a map that shows the extension of the ancient walls compared to the modern city.

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THE POPES' WALLS
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