Technology
The ancient Romans also had a complex system of aqueducts, which were used to transport water across long distances. The first Roman aqueduct was built in 312 BCE. The eleventh and final ancient Roman aqueduct was built in 226 CE. Put together, the Roman aqueducts extended over 450 kilometers, but less than seventy kilometers of this was above ground and supported by arches.
Zaghouan Aqueduct
The date of the construction of the aqueduct is not entirely clear. Sources mention a visit by the Emperor Hadrian in 128, with which a five-year-long drought is meant to have come to an end. The water shortage resulting from the drought might have convinced him that the people should not rely only on rainwater any more. A second event which might have inspired it was the opening of the Baths of Antonius in Carthage in 162. These facilities on the same scale as the Imperial baths in Rome demanded a steady supply of water, which could not be fulfilled with rain water.