Inland waterways

Rivers, canals and lakes have long been used to carry goods and people. How useful an inland waterway is depends on its width and depth, a continuous flow of water all year, and the technology available.

In India, rivers were once important trade routes, but they lost importance because of competition from railways, the diversion of water for irrigation (which made rivers too shallow), and poor maintenance.

Some of the world's great inland waterways:

• The Rhine flows through Germany and the Netherlands. It is navigable for 700 km, from Rotterdam at its mouth to Basel in Switzerland, and passes through the Ruhr coalfield, a major industrial region. It is the world's most heavily used inland waterway.
• The Danube serves eastern Europe, flowing into the Black Sea.
• The Volga, in Russia, provides a navigable waterway of 11,200 km and drains into the Caspian Sea. Canals link it to Moscow and to the Don river.
• The Great Lakes-St Lawrence Seaway lets ocean ships sail deep into the heart of North America.
• The Mississippi-Ohio waterway joins the interior of the USA with the Gulf of Mexico.