Upper Rhine Plain

The Upper Rhine Plain, Rhine Rift Valley or Upper Rhine Graben is a major rift, about 350-kilometre-long and on average 50-kilometre-wide , between Basel in the south and the cities of Frankfurt/Wiesbaden in the north. Its southern section straddles the France–Germany border. It forms part of the European Cenozoic Rift System, which extends across Central Europe. The Upper Rhine Graben formed during the Oligocene, as a response to the evolution of the Alps to the south. It remains active to the present day. Today, the Rhine Rift Valley forms a downfaulted trough through which the river Rhine flows.

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