The Roman Empire came to rely on a network of tunnels and arcades to supply their cities of water. The imperial baths, the monumental fountains, the watered terraces, the public water spouts, the pressurized plumbing, the flushing of the sewers, all required the Roman aqueducts to deliver a large and steady volume of water.
Even in ancient times the Roman aqueduct arches were showpieces, structures designed for their appearance as well as their function. Powered entirely by gravity, they could carry large amounts of water very efficiently.
Although the Romans took aqueduct building to new heights, they were not the first civilization to channel water long distances. The Assyrians developed a technique of tunneling that continues to be used today in the Iranian plateau and still supplies water. In the ancient Greek world several cities had aqueducts that pre-date Roman occupation.
Aqueducts in the Roman Empire
The first aqueduct in the city of Rome was the Aqua Appia, built in 312 BC during the Roman Republic. The combined length of all the aqueducts built in ancient Rome is about 800 km (500 miles). However, only 47 km (29 miles) were above ground, as most Roman aqueducts ran beneath the surface of the ground.
Many of the most impressive remains of Roman aqueducts are not in Rome itself, but in the former provinces, such as the famous Pont du Gard in southern France. This ancient bridge, part of an aqueduct that supplied water to ancient Nimes, is renowned both by its height (49 meters or 160 ft) and its beauty. The aqueduct consist of three tiers of arches and was built out of limestone blocks without the use of mortar.
Another Roman aqueduct bridge of architectural fame, almost as high as the Pont du Gard, can be found in Segovia, Spain. Some of the city’s water is still carried on a structure that dates back to the reign of Emperor Claudius.