Viaduct with larger spans, typically lack sufficient horizontal and vertical clearance for large ships. See the Chesapeake Bay Bridge-Tunnel. The Millau Viaduct is a cable-stayed road-bridge that spans the valley of the river Tarn near Millau in southern France. Designed by the French bridge engineer Michel Virlogeux, in collaboration with architect Norman Robert Foster, it is the tallest vehicular bridge in the world, with one pier's summit at 343 metres (1,125 ft)—slightly taller than the Eiffel Tower and only 38 m (125 ft) shorter than the Empire State Building. It was formally dedicated on 14 December 2004 and opened to traffic
Millau Viaduct World Wildlife Fund (WWF), "France Nature Environnement", the national federation of motorway users, and Environmental Action. Opponents advanced several arguments: Two weeks after the laying of the first stone on December 14, 2001, the workers started digging the deep shafts. There were four shafts per pylon; deep and in diameter, assuring the stability of the pylons. At the bottom of each pylon, a tread of in thickness was installed to reinforce the effect of the deep shafts. The of concrete necessary for the treads was poured at the same time. In March 2002, the pylons emerged from the ground. The