The Millau Viaduct was put into service in December 2004. It receives hundreds of thousands of visitors each year, either motorists or tourists and architecture enthusiasts wishing to gaze at a structure unique in the world. A viaduct and a bridge fulfill the same role: allowing a spanned track to cross an obstacle. The difference between the two is that a bridge connects two banks, while a viaduct links two elevated points. The Millau Viaduct resulted from a Franco-British collaboration between the chief engineer Michel Virlogeux and the English architect Lord Norman Foster.