Dortmund is a city in Germany. It is located in the Bundesland of North Rhine-Westphalia. Its population of 571,403 makes it the 8th largest city in Germany. Dortmund is the largest city by area and population in the Ruhr Area, an urban area with some 5.1 million inhabitants which is the largest urban agglomeration in Germany. Dortmund is also a part of the larger Rhine-Ruhr metropolitan region of more than 12 million people.The river Ruhr flows south of the city, and the small river Emscher flows through the municipal area. The Dortmund-Ems Canal also terminates in the Dortmund Port, which is the largest European canal port, and links Dortmund to the North Sea.Dortmund is known as Westphalia's "green metropolis". Nearly half the municipal territory consists of waterways, woodland, agriculture and green spaces with spacious parks such as Westfalenpark and the Rombergpark. This contrasts with nearly a hundred years of extensive coal mining and steel milling within the city limits.