RHONE RIVER

river of Europe, an historic southern gateway, and the only major river of the continent that flows directly to the Mediterranean Sea. Alpine in character, the scenic and sometimes wild course of the Rhne has been shaped by neighbouring mountain systems. Emerging from the Rhne Glacier in the Alps of south-central Switzerland, the river flows generally westward through a series of structural troughs and wider intermontane valleys before entering Lake Geneva. Exiting that lake through the city of Geneva, the Rhne enters France, transiting the Jura Mountains in a complicated zigzag course before merging with its principal tributary, the Sane, at the city of Lyon. Turning south, the Rhne continues to receive powerful tributaries of Alpine origin (including the Isre, Durance, and Ardche) as it flows through gorges and basins hollowed out by the glaciers of the Ice Age between the Alps and the Massif Central. The Rhne enters the Mediterranean through the braided channels of its alluvial deposits west of Marseille. The 505-mile- (813-kilometre-) long river occupies a drainage basin of about 37,750 square miles (97,775 square km), and its average annual discharge near the river's mouth is 59,000 cubic feet per second (1,700 cubic m per second). The strong gradient and gravel shoals of even the lower stretches of the Rhne long proved an obstacle to navigation. Between the late 1940s and late 1970s, however, a French government-sponsored multipurpose scheme regularized the river's flow south of Lyon through a series of dams and canals. Hydroelectric and nuclear power stations were constructed along the river, and irrigation canals were more adequately utilized; and so by the late 1970s Lyon had become regularly navigable to barges of from 3,000 to 5,000 tons. The hydroelectric potential of the upper Rhne has been effectively harnessed by the Swiss. A canal under construction connecting the Sane River north of Lyon to the Rhine River will eventually allow large barges to cross Europe from the North Sea to the Mediterranean Sea. The Rhine, Rhne, and Seine river basins and their drainage network. historic river of Switzerland and France and one of the most significant waterways of Europe. It is the only major river flowing directly to the Mediterranean Sea and is thoroughly Alpine in character. In this respect it differs markedly from its northern neighbour, the Rhine, which leaves all of its Alpine characteristics behind when it leaves Switzerland. The scenic and often wild course of the Rhne, the characteristics of the water flowing in it, and the way it has been used by humans have all been shaped by the influences of the mountains, right down to the river mouth, where sediments marking the Rhne's birth in an Alpine glacier are carried into the warmer waters of the Mediterranean. The Rhne is 505 miles (813 kilometres) long and has a drainage basin of some 37,750 square miles (97,775 square kilometres). The course of the river can be divided into three sectors lying, respectively, in the Alps, between the Alps and the Jura Mountains and through the latter, and finally in the topographical furrow of Alpine origin running from the city of Lyon to the sea. Additional reading Much of what has been written on the Rhne is included in general and regional geographies of Switzerland, France, and western Europe, such as Aubrey Diem, Western Europe, a Geographical Analysis (1979). Daniel Faucher, L'Homme et le Rhne (1968), is a historical survey of water resources development and economic conditions; it is supplemented by earlier exhaustive works by a hydrologist of world reputation, Maurice Parde, Le Rgime du Rhne: tude hydrologique (1925), continued in his Quelques Nouveautes sur le rgime du Rhne (1942). A short account focusing on economic conditions, from the series Problem Regions of Europe, is Ian B. Thompson, The Lower Rhne and Marseille (1975). Aubrey Diem