Why we still can’t escape ancient Rome’s most successful housing idea

This summer has not been easy for European holidaymakers. Temperatures through the roof. Wildfires across Spain, France and Italy. The EasyJet meltdown, with its nights on the floor at Gatwick. Still… It could have been worse. We could have been stuck in the city, cooped up inside a condominio, the shared apartment block where most Italians live.

Few people realise that the condominio is one of Italy’s most successful inventions, exported around the world. Its origins go back to the Casa di Diana, a second-century AD insula. While the patrician families spread horizontally through their opulent villas, the plebs went vertical. Floor upon floor, family upon family.