The Rioni of Rome

What a rione is

A rione is a traditional district of the city of Rome. The word has been used since the fourteenth century and comes from the Latin regio, region, which became rejones in the Middle Ages. Rome's historic center is made of twenty-two of them, each with a number in Roman numerals, a name and a coat of arms. On street plaques and maps a rione is written with the letter R and its number: Trastevere is R. XIII, Prati R. XXII. Everything outside them belongs to the larger quarters of the modern city, marked Q.

For a visitor the rioni are the most useful way to hold the city in your head. A sight on this site always carries its rione: the Colosseum stands in XIX, Celio; the Pantheon in IX, Pigna; Piazza Navona in VI, Parione. Two of the eighteen stand outside the rioni altogether, and two more stand in another country: St. Peter's and the Vatican Museums are in Vatican City.

From regions to rioni

According to tradition, King Servius Tullius first divided the city into four regions. Augustus made fourteen, which lasted through the empire, and all but one, Trans Tiberim, lay on the left bank of the Tiber. After the fall of Rome the population shrank and the division was lost. In the twelfth century the people began, unofficially, to speak of twelve districts, still called regio in Latin and rione in the spoken tongue. By the thirteenth century there were thirteen, each headed by an officer called the caporione.

In 1586 Pope Sixtus V added Borgo, the district between the Vatican and the river, as the fourteenth. The numbers held until Rome became the capital of Italy. In 1874 Esquilino was carved out of Monti to make fifteen; in the early twentieth century others were split and the first districts beyond the walls were added, and in 1921 the count reached twenty-two, with Prati the last. Since 2013 all twenty-two have belonged to the first municipio of the city.

The marble plaques of 1744

In 1744 Pope Benedict XIV, tired of disputes over where one district ended and the next began, had Count Bernardini redraw the boundaries. Marble plaques marking the border of each rione were set into the walls of the houses along its edges that year, and many of them are still there. Look up at street corners in the old center and you will see them, carved with the rione's name and number, a small record of eighteenth-century administration that doubles as a map.

Napoleon's French government later reorganized the city into eight districts and fixed a name plate in every street; the older rioni came back after his fall.

Reading the names

The names are a history of the city in miniature. Some come from ancient buildings: Colonna from the Column of Marcus Aurelius, Castro Pretorio from the barracks of the Praetorian Guard, Parione from a great wall, perhaps part of Domitian's stadium. Some come from the land: Monti from its hills, Regola from the sand the Tiber left after floods, Ripa from the riverbank. Some come from churches, like Sant'Eustachio and San Saba, and one from a giant bronze pine cone, Pigna, whose namesake now stands in a Vatican courtyard.

Testaccio takes its name from Monte Testaccio, a hill built entirely of broken clay amphorae from the river trade of antiquity, still a rich source of evidence about everyday Roman life. The people of Regola were nicknamed tail-eaters, after the oxtail stew, coda alla vaccinara, made by the rione's many butchers.

Their coats of arms are just as specific: three green mountains for Monti, three swords for Trevi, a rudder for Ripa, an amphora for Testaccio, the silhouette of Hadrian's tomb for Prati.

Two rioni with walls of their own

Two districts were once enclosed inside the city. In 1555 Pope Paul IV, by the bull Cum nimis absurdum, confined the Jews of Rome to a ghetto in Sant'Angelo, the smallest rione, in the low ground by the Tiber near the Theatre of Marcellus, an area now bounded by Via del Portico d'Ottavia and the river. Apart from brief periods under the Roman Republics and Napoleon, whose troops made a point of pulling down its walls, the ghetto remained under papal control until the capture of Rome in 1870.

Borgo, across the river, has walls for the opposite reason. In the ninth century the district around St. Peter's was plundered by Saracen raiders and swept by fire, the fire of 847 that Raphael later painted in the Vatican. Pope Leo IV answered by enclosing it, walking barefoot with the clergy and people around the circuit of the new walls on 27 June 852, and the district took the name the Leonine City. Its coat of arms still shows a lion.

The walls as a boundary

Most of the rioni lie within the Aurelian Walls, built between 271 and 275 under the emperor Aurelian. The walls ran for about twelve miles around the seven hills, the Campus Martius and, across the river, Trastevere, and they defended the city until 20 September 1870, when Italian troops breached them near the Porta Pia and took Rome. Long stretches still stand, and the gates still mark the way out: the Appian Way leaves by the Porta San Sebastiano, and the road from the north enters at Piazza del Popolo.

The rioni added after 1870 were built on the villas and vineyards inside the walls, or just beyond them. Ludovisi was laid out from 1886 over the gardens of the Villa Ludovisi; Prati was the only one built outside the walls of Pope Urban VIII.

Using the numbers

The order has a logic. The low numbers, I to XII, are the old districts on the left bank, from Monti on its hills to the bend of the river and down to the Aventine. XIII is Trastevere, across the water, and XIV is Borgo, beside the Vatican. XV to XXI were created from 1874 onward, mostly on the edges of the old city, and XXII, Prati, lies north of Borgo.

If you are planning a stay, the neighborhoods page groups the rioni by what they are like to stay in, and the itineraries page follows them on foot.