Conventillos, a Spanish word meaning small convents, were enormous one and two story buildings. Like a convent, they were divided into scores of one-room cell-like flats. But rather than housing religious sisters as their name suggests, conventillos were home to the poor. Each small flat, no more than 15 meters square, slept a family or group of men numbering 8 to 10. Conventillos had neither electricity nor running water and most didn't have windows either. Residents shared a common toilet. They cooked and washed in a central courtyard. The front door was the flat's one source of light and air. Conventillos were frigid in winter and sweltering in summer. These tenement houses were built in Buenos Aires in the late 1800s. They housed the city's immigrants, Italians, Spaniards, Arabs and Jews.