Eifel Aqueduct
North Rhine-Westphalia, Germany
The Eifel Aqueduct was one of the longest aqueducts of the Roman Empire. The aqueduct, constructed in AD 80, carried water some 95 kilometres (59 mi) from the hilly Eifel region of what is now Germany to the ancient city of Colonia Claudia Ara Agrippinensium (present-day Cologne). If the auxiliary spurs to additional springs are included, the length was 130 kilometres (81 mi). The construction was almost entirely below ground, and the flow of the water was produced entirely by gravity. A few bridges, including one up to 1,400 metres (0.87 mi) in length, were needed to pass over valleys. Unlike some of the other famous Roman aqueducts, the Eifel aqueduct was specifically designed to minimize the above-ground portion to protect it from damage and freezing.
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