It is the world's tallest bridge, at 343 m tall at its highest pillar, the Millau Viaduct in Southern France is almost a third taller than any other bridge in the world. A freeway in the sky, the bridge crosses the river Tarn in France and can save travelers almost an hour of travel between France and the Mediterranean. It also removes the traffic congestion once faced in the town of Millau. The episode documents the difficulties that the crew had to face, and the challenging processes that were used in its construction. The documentary contains a few words from the mayor of Millau, Jacques Godfrain, the bridge architect, Norman Foster, and designer, Michel Virlogeux.