The Rhine is one of the longest rivers in Europe, with its source in Switzerland. It flows through various countries and past various towns to the North Sea.
When we talk about the Rhine, we mean the river as shown on the first map without the smaller rivers that flow into it. Because there are a lot of these!
The second map shows the catchment area. This is the area in the dark colour. Rain or snow that falls in the catchment area passes through small rivers, streams and groundwater to end up in the Rhine. The water flows via the Rhine to the North Sea. Rain that falls just outside this area travels to the sea via another river. Raindrops that fall just outside the Rhine catchment area in Switzerland are most likely to end up in the Mediterranean, via rivers like the Rhône in France or the Po in Italy.
Rain that falls in the catchment area of the Danube ends up in the Black Sea.
The catchment area lies in nine countries. You can see the flags and abbreviations for these countries on the maps.
DE – Germany
BE – Belgium
NL – The Netherlands
FR – France
LU – Luxembourg
CH – Switzerland
AT – Austria
IT – Italy
LI - Liechtenstein
Many rivers and streams flow into the Rhine, these are called tributaries. In the Netherlands the Rhine divides into many different rivers that carry the water to the sea.
The catchment area of the Rhine also includes many well-known tributaries, such as the Moselle, the Main, the Saar, the Neckar and the IJssel.