Tarn (river) a mean flow of approximately . The Millau Viaduct spans the valley of the Tarn near Millau, and is now one of the area's most popular attractions. The tributaries of the Tarn include: The Tarn separates the Narbonne and Aquitaine basins. The Tarn passes through the following departments and towns: The Millau Viaduct, the tallest bridge in the world, carrying the A75 autoroute across the Tarn Gorge near Millau, opened in December 2004. The Tarn is famous for its brutal floodings, which are the most dangerous in Europe along with the Danube. The flooding of March 1930 saw the Tarn
Pit River Bridge the upper deck and on the lower deck. With a height of above the old Pit River bed, it is structurally the highest double decked bridge in the United States; however, today the bridge sits only about above the water when Shasta Lake is full. At the time it was built, the highway on the bridge was signed as U.S. Route 99 and the rail line was owned by Southern Pacific. The "Coast Starlight", the passenger train line operated by Amtrak that runs from Los Angeles north to Seattle, also uses the bridge. The bridge is officially known as the