Hagen is the 41st-largest city in Germany. The municipality is located in the state of North Rhine-Westphalia. It is located on the south eastern edge of the Ruhr area, 15 km south of Dortmund, where the rivers Lenne and Volme meet the river Ruhr. As of 31 December 2010, the population was 188,529.
The city is home to the FernUniversität Hagen, which is the only state-funded distance education university in Germany. Counting more than 67,000 students, it is the largest university in Germany.