Millau Viaduct
Norman Foster & Partners

Photo ©Thomas Mayer

Bridges are often considered to belong to the engineer's realm rather than the architect's. But the architecture of infrastructure has a powerful impact on the environment.

The Millau Viaduct, designed in collaboration with engineers, illustrates how the architect can play an integral role in bridge design.


Photo ©Thomas Mayer

Photo ©Thomas Mayer

Located in southern France, the bridge connects the motorway from Paris to Barcelona at the point where it meets the River Tarn, which runs through a wide gorge between two plateaux.


Photo ©Thomas Mayer

A reading of the topography suggested two possible approaches: to celebrate the act of crossing the river, the geological generator of the landscape; or to articulate the challenge of spanning the 2.5 kilometres from one plateau to the other in the most economical manner.

The structural solution follows from the latter philosophical standpoint. The bridge has the optimum span between cable-stayed columns. It is delicate, transparent, and uses the minimum material, which makes it less costly to construct.


Photo ©Thomas Mayer

Photo ©Thomas Mayer

Each of its sections spans 342 meters and its columns range in height from 75 meters to 235 meters, with the masts rising a further 90 meters above the road deck.


Photo ©Thomas Mayer

Photo ©Thomas Mayer

To accommodate the expansion and contraction of the concrete deck, each column splits into two thinner, more flexible columns below the roadway, forming an A-frame above deck level.


Photo ©Thomas Mayer

This structure creates a dramatic silhouette and crucially, it makes the minimum intervention in the landscape.


Drawing courtesy Foster & Partners