By Allan Little
BBC News, Millau, France
There is something almost spectral about the vision of the new bridge across the Tarn Valley at Millau.
The bridge will help cut down travelling times to the south
It is almost as though it is not connected to the normal laws of gravity.
The ribbon of steel that stretches for 2.5km (1.5 miles) across the valley is so thinly stretched, it appears to be elevating or suspended from the clouds.
The impression from either end of the bridge is of sailboats in a sea of mist.
Designed by the British architect Norman Foster, the structure is very much the product of a French vision.
France wants to associate itself with iconic modernity.
The bridge was built by the successor of the company that built the Eiffel Tower. And in its own way, this is a 21st Century version of the famous Paris landmark.
The River Tarn which flows beneath the bridge is small, but it is one that has caused a lot of congestion over the decades.
Much of the traffic which comes down from central and northern areas of France, heading for the densely populated areas of the Mediterranean coast, has to pass through the small town of Millau.
There are something like 10,000 vehicles a day, and in the congested summer months, this can delay journeys by about four or five hours.
As well as relieving this congestion, the impact of the bridge will have economic as well as aesthetic consequences.
It will affect the efficiency of France's road haulage as well as its tourist network.
With all of these advantages, it is no surprise that President Chirac came to open the bridge officially on Tuesday and, by implication, associate himself with such an architectural achievement.
In engineering terms, it is the tallest bridge in the world.
The ribbon of steel which forms the highway in the sky is 270m (885ft) above the river, but the central pillar is 343m (1125ft) high.
That makes it taller than the Eiffel Tower and four times the height of Big Ben in central London.