The "Rioni" of Rome
The districts of Rome were defined in a precise manner in 1743 by Benedictus IV. The area inside the walls was divided into 14 districts called Rioni. One of the criteria followed in the definition of the districts was to have an even distribution of the population, at the time grouped near the river. This explains why the area of the
rioni is so different.
The 14 rioni of Rome on a late XIXth century map
The decision to divide Rome into fourteen quarters was in part suggested by the fact that also Ancient Rome was divided into fourteen regiones (hence rioni); thus Rome was also called Urbs regionum quatuordecim.
The division of Ancient Rome into fourteen regiones was introduced by Augustus to provide Rome with a new administrative structure which could meet the requirements of a very large city. The regiones were not limited by the walls which were built nearly 300 years later and they were only known by their number (as we still do for the arrondissements of Paris), but over time they were referred to by mentioning a monument or a hill included in the region.
The table below provides an approximate relationship between the modern (in blue) and the ancient (in red) division of Rome.
It shows how the most populated areas of Ancient Rome (on the hills) were abandoned in favour of locations close to the river.
For this reason three modern rioni (Monti, Campitelli, Ripa) covered the same area of 10 ancient regiones, while a single regio (Circus Flaminius) was in the XVIIIth century divided into more than 6 rioni.
I-Monti was divided into 3 rioni (Monti, Esquilino, Castro Pretorio);
II-Colonna was divided into 2 rioni (Colonna and Ludovisi);
III-Trevi was divided into 2 rioni (Trevi and Sallustiano);
X-Campitelli was divided into 2 rioni (Campitelli and Celio);
XII-Ripa was divided into 3 rioni (Ripa, Testaccio, San Saba);
the area north of Porta Castello became a new rione: Prati.
Today (2004) Rome is divided into 20 municipalities: the first one includes all the historical rioni, with the exception of Borgo.
You can now start your tour of the Rioni.