Regio [pl. –es] - During the time of the Republic, Rome existed on (6/7) hills  and was divided into four equal districts that existed within the Pomerium and went in a counter-clockwise fashion. These districts simply were protected by the Servian Wall  and with the center probably between the Velia and Oppian Hill:
Regio I Suburana
Regio II Esquilina
Regio III Collina
Regio IV Palatina
 Urbs Septicollis – According to classical thought, Rome is a city on seven hills. However, the plateau of the Esquiline hill lies outside the Servian Wall [Rome originally started within these walls]. So technically, there are only six hills.
 Pomerium – Rome’s religious culture began as animism, basically being both material and spiritual. Within these animistic thoughts, there is a spiritual border that surrounds early Rome, called the Pomerium, which one can basically cross just by going through the Servian Wall.
 Servian wall – Rome’s first walled fortification that encompassed the city within it was Servian Wall, built by probably Servius Tullius and was meant to protect Rome in its youth.
However, when the city’s population grew much larger, four districts were just not enough. Therefore, in 7 B.C., the imperator Augustus redistricted Roma, according to the population, into fourteen new districts (that remained unchanged until the collapse of the Western Empire). Each district would have two vicimagistri that served as local mayors and also leaders to the vici. Each district also had at least one major police and fire station, which the number would grow later on. However, by this time, Rome had grown beyond the Servian Wall and it took a few more centuries until a new fortification called the Aurelian Wall  was built:
Regio I. Porta Capena (Capena Gate)
Regio II Caelimontium (Caelian Hill)
Regio III Isis et Serapis (temple are of Isis and Serapis)
Regio IV Templum Pacis (Temple of Peace)
Regio V Esquiliae (Esquiline Hill)
Regio VI Alta Semita (High Lane)
Regio VII Via Lata (Broad Street)
Regio VIII Forum Romanum (Roman Forum)
Regio IX Circus Flaminius (Flaminian Raceway)
Regio X Palatium (Palatine Hill)
Regio XI Circus Maximus (Great Raceway)
Regio XII Piscina Publica (Public Pool)
Regio XIII Aventinus (Aventine Hill)
Regio XIV TransTiberim (Across the Tiber)
 Vicomagistri – Each Roman district had two local magistrates.
 Vicus [pl. -i] – Within the Roman districts exists numerous neighborhoods, termed vici. The concept of vici is just as the same the modern understanding of a neighborhood. A normal vicus would have contained an aedicule (local shrine) or fountain as the central plaza(forum) and a police force called the vigiles. Somewhere nearby was a firestation for surrounding vici.
 Aurelian Wall – By this time, the Servian Wall had been decaying for some time. However, the need for a new wall did not come immediately until the barbarian invasions of Italy, which prompted Emperor Aurelian to build the Aurelian Wall after an encounter/victory over the Vandals near Rome.
This article was written by forum member FLavius Valerius Constantinus