The Elbe River forms one of the largest river systems of central Europe. It originates in the Northwest part of the Czech Republic before traversing Germany and emptying into the North Sea. Its basin covers different geographical regions from middle mountain ranges in the west and south to large flatlands and lowlands in the central, northern and eastern part of the basin. The Elbe has been navigable by commercial vessels since 1842, and provides important trade links as far inland as Prague. The river is linked by canals to the industrial areas of Germany and to Berlin. The Elbe-Lübeck Canal also links the Elbe to the Baltic Sea.