that of modern-day cities like New York City or modern Rome. Most water was for public use, such as baths and sewers. De aquaeductu is the definitive two-volume treatise on 1st-century aqueducts of Rome, written by Frontinus.

The aqueducts could stretch from 10 - 100 km long, and typically descended from an elevation of 300 m -2 abbr=on above sea level at the source, to 100 m when they reached the reservoirs around the city. Roman