It would have never occurred to me to take a ride in an aqueduct, but now I want to! Before railroads, before highways, Britain built many elevated waterways to transport cargo from place to place. Many are still there, and they are fascinating. Shown is the Pontcysyllte Aqueduct in Wales, which is a UNESCO World Heritage Site and is open for tourist traffic. See ten such UK aqueducts at WebUrbanist. Link