Pont du Gard - The Roman Aqueduct of Nîmes, France (123/418)

The Pont du Gard was built shortly before the Christian era to allow the aqueduct of Nîmes, almost 50 kilometres long, to cross the Gard River. The hydraulic engineers and Roman architects who conceived this bridge, which is almost 50 m high over three levels - the longest measuring 275 m - created a technical as well as artistic masterpiece.