<Tr> <Td_colspan="2"> Map of the Rhine basin </Td> </Tr> <Tr> <Td_colspan="2"> Wikimedia Commons: Rhine </Td> </Tr> <P> The Rhine (Latin: Rhenus, Romansh: Rein, German: Rhein, French: le Rhin, Dutch: Rijn) is a European river that begins in the Swiss canton of Graubünden in the southeastern Swiss Alps, forms part of the Swiss - Austrian, Swiss - Liechtenstein, Swiss - German and then the Franco - German border, then flows through the Rhineland and eventually empties into the North Sea in the Netherlands . The largest city on the river Rhine is Cologne, Germany, with a population of more than 1,050,000 people . It is the second - longest river in Central and Western Europe (after the Danube), at about 1,230 km (760 mi), with an average discharge of about 2,900 m / s (100,000 cu ft / s). </P> <P> The Rhine and the Danube formed most of the northern inland frontier of the Roman Empire and, since those days, the Rhine has been a vital and navigable waterway carrying trade and goods deep inland . Its importance as a waterway in the Holy Roman Empire is supported by the many castles and fortifications built along it . In the modern era, it has become a symbol of German nationalism . </P>

How long is the rhine germany's longest river