Witten is a mid-sized city on the southern edge of the Ruhr area, sitting where the Ruhr River cuts through wooded hills before entering the industrial flatlands to the north. It is home to the University of Witten/Herdecke, Germany's first private university, which gives the place a younger feel than many of its Ruhr neighbors. The real draw for visitors is the Muttental mining trail, a walking route through the valley south of town that passes old mine shafts, restored pit-head buildings, and geological outcrops -- a compact open-air museum of the region's coal-mining origins that predates the big industrial operations most people associate with the Ruhr.
The town center is pleasant if unremarkable, rebuilt after wartime damage in the functional style of the 1950s. The Ruhr riverfront is the more appealing part, with walking and cycling paths that connect Witten to the wider RuhrtalRadweg network. The Hohenstein park on the bluffs above the river offers good views and has a small wildlife enclosure popular with families. If you are exploring the Ruhr area beyond the big cities, Witten makes a reasonable stop -- less polished than Essen or Dortmund, but with an easy, unpretentious character of its own.