Visitors to Rome are often astonished not so much by the big famous fountains that dot the city but by the smaller flows that gush or trickle from what seems like every street corner. All that water, going to waste. Those drinking fountains – known locally as nasoni or big noses – deliver endless streams of delicious, cold water night and day, summer and winter, and it surprises many people to learn that public water fountains have been a feature of the city since well before the Republic. Indeed, clean water was the right of every Roman citizen.

Dotted around the city and its environs you’ll also see traces of the engineering that made the public drinking fountains possible: the long, straight lines of the aqueducts and, more often, the occasional broken arch. In many cases, the city’s water supply still traces the routes of the aqueducts and even uses their structures. There is a lot of information about the waters of Rome online, but nothing beats a personal tour guide. I was lucky enough to persuade Katherine Rinne, who supplies a lot of the online information, to show me how it all worked.