Verdon Gorge

The Verdon Gorge (in French: Gorges du Verdon or Grand canyon du Verdon), in south-eastern France (Alpes-de-Haute-Provence), is a river canyon that is often considered to be one of Europe's most beautiful. It is about 25 kilometres long and up to 700 metres deep. It was formed by the Verdon River, which is named after its startling turquoise-green colour, one of the canyon's most distinguishing characteristics. The most impressive part lies between the towns of Castellane and Moustiers-Sainte-Marie, where the river has cut a ravine up to 700 metres down through the limestone mass. At the end of the canyon, the Verdon river flows into the artificial lake of Sainte-Croix-du-Verdon (in French: Lac de Sainte-Croix).

Because of its proximity to the French Riviera, the canyon is very popular with tourists, who can drive around its rim, rent kayaks or hike.

http://en.wikipedia.org/wiki/Gorge_du_Verdon