insula

Remains of the top floors of an insula near the Capitolium and the Insula dell'Ara Coeli in Rome In Roman architecture, an insula (Latin for "island", pl.: insulae) was one of two things: either a kind of apartment building, or a city block. This article deals with the former definition, that of a type of apartment building.

Insulae housed most of the urban citizen population of ancient Rome's massive population ranging from 800,000 to 1 million inhabitants in the early imperial period. Residents of an insula included ordinary people of lower- or middle-class status (the plebeians) and all but the wealthiest from the upper-middle class (the equites).