Roman aqueduct
Rome's first aqueduct was built in 312 BC, and supplied a water fountain at the city's cattle market. By the 3rd century AD, the city had eleven aqueducts, sustaining a population of over a million in a water-extravagant economy; most of the water supplied the city's many public baths. Cities and towns throughout the Roman Empire emulated this model, and funded aqueducts as objects of public interest and civic pride, "an expensive yet necessary luxury to which all could, and did, aspire".
Romanization of Hispania
An important town needed a constant water supply for the thousands of people gathered in one place which could be sometimes several miles away from natural water source. To achieve this continuous flow of water the Romans built aqueducts.
The Roman aqueducts, despite their appearances, were built mostly underground. However, they are now known as the monumental aqueducts built to bridge geographic barriers in order to give a continuous water channel. The slenderness of this type of construction, along with the tremendous height reached by some of them, makes them the most beautiful works of civil engineering of all time, especially taking into account the difficulties overcome to build them.