from Wikipedia Rotterdam:
Rotterdam (pronunciation (help·info)) is the second largest municipality by population in the Netherlands, after the capital Amsterdam, and the largest city in the province of Zuid-Holland (South Holland). The port of Rotterdam is the largest in Europe and was the world's busiest port from 1962 to 2004, until it was overtaken by Shanghai. Rotterdam is situated on the banks of the river Nieuwe Maas ('New Meuse'), one of the channels in the delta formed by the Rhine and Meuse rivers. The name Rotterdam derives from a dam in the Rotte river.