14 regions of Augustan Rome

In 7 BC, Augustus divided the city of Rome into 14 administrative regions (Latin regiones, sing. regio). These replaced the four regiones or "quarters" traditionally attributed to Servius Tullius, sixth King of Rome. They were further divided into official neighborhoods (vici).

Originally designated by number, the regions acquired nicknames from major landmarks or topographical features within them.

Regio I took its name from the Porta Capena ("Gate to Capua"), a gate through the Servian Walls which the Appian Way takes to get into the city. Beginning from this to the south of the Caelian Hill, it runs to the future track of the Aurelian Walls.

Regio II encompassed the Caelian Hill.

Regio III took its name from the sanctuary of Isis, in the area of the modern Labicana street, containing the valley which was to be the future site of the Colosseum, and parts of the Oppian and Esquiline hills.

Regio IV took its name from the Temple of Peace built in the region by Vespasian. It includes the valley between the Esquiline and the Viminal hills, the popular area of the Subura, and the Velian Hill (the hill between the Palatine and the Oppian Hill, removed in the early 20th century to make way for the via dei Fori Imperiali, the street passing between the Forum Romanum and the Forum of Augustus).

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