Of the second wall, the Servian Wall, much remains but its chronology is in dispute; was it built, razed and rebuilt? For over 400 years Rome relied on the Tiber and springs for its water supply, before they built their first aqueduct.
2. Imperial Walls and Aqueducts
As the Roman Empire grew so did its capital. A total of 11 aqueducts were built to service Rome. And the population spread well beyond the circuit of the Servian Wall. As long as peace reigned, there was no problem. But as the Empire began to crumble, the need for a new wall became paramount, so the Aurelian Wall was built. The wall survived the fall of the Empire, the aqueducts did not.