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Roman Eifel Aqueduct

The Roman Eifel Aqueduct, also known as the Roman Canal, supplied the ancient city of Colonia Claudia Ara Agrippinensium, modern-day Cologne, with fresh drinking water. It was one of the longest aqueducts north of the Alps.
History+
Around 80 AD, the Eifel Aqueduct was built in the Northern Eifel to supply the rapidly growing Roman metropolis with high-quality spring water. Previously, the city used an older pipeline, the Vorgebirgsleitung, which tapped into springs and streams of the Ville. When its capacity and water quality were no longer sufficient, the decision was made to construct the new aqueduct, approximately 95.4 kilometers long. With feeder lines, the total length even reached 130 kilometers.
Source: Wikipedia · Licence: CC BY-SA 4.0
This description draws on the facts documented in the linked Wikipedia article; Wikipedia content is licensed under CC BY-SA 4.0. Wording and editing: Mobile History.
Location: 50.6123, 6.7879