Four-fifths of the Rhine traffic is made up of fuels, ores and cereals, all heavy commodities. Trade in them thrives best when they may be shipped by water routes. Coal at present constitutes the principal cargo. Originating in the Ruhr district it supplies Holland and Belgium at the mouth of the river, reaches Switzer land and even Italy to the South and supplies the extensive in dustrial and domestic demands of the territory in between. Its presence has given value to the ores which form the second most important cargo and the two in combination have given rise to the extensive metallurgical industries of the Rhine region which have built up the Rhine cities and increased the density of popula tion. In the demands of the latter originates the cereal cargo, made necessary since the Rhine raises little of its foodstuffs. The cereals come principally from Russia, Rumania, the United States and Argentina, being trans-shipped from the river-mouth ports. London, Hamburg, Bremen and the chief Baltic ports also par ticipate in the Rhine traffic. These extensive ramifications have made the control of Rhine navigation an international problem rather than one affecting only Rhine states.
The commerce carried on by the river itself is supplemented by the numerous railways which skirt its banks and converge to its principal towns. Before the introduction of railways, there were no permanent bridges across the Rhine below Basle; but now trains cross it at a dozen different points in Germany and Holland.
The Rhine has always exercised a fascination over the German mind. "Father Rhine" is the centre of the German's patriotism and the symbol of his country. In his literature it has played a prominent part from the Nibelungenlied to the present day; and its romantic legends have been alternately the awe and delight of his childhood. The Rhine was the classic river of the middle ages.
But of late years the beauties of the Rhine have become sadly marred; the banks in places, especially between Coblenz and Bonn, disfigured by quarrying, the air made dense with the smoke of cement factories and steam-tugs, commanding spots falling a prey to the speculative builder and villages growing up into towns.
For the demilitarization of the Rhine under the Versailles TREATY see RHINELAND, THE, below.