Borken is a small town with about 13,000 inhabitants in the Schwalm-Eder district in northern Hesse, Germany.
The town is a former centre for brown coal mining and coal-fired electrical generation in Hesse. The coalmine, unlike those in other regions, also had underground workings. After a major disaster – namely a coal dust explosion – the mine was shut down on 1 June 1988.
Since that time, the former coal pits have been redeveloped into recreation areas with lakes, nature areas – some actually protected by law – and sporting grounds. Among these areas are der Borkener See with its nature reserve, der Singliser See with windsurfing, and die Stockelache, used as a bathing lake.
Wikipedia https://en.wikipedia.org/wiki/Borken,_Hesse
Coordinates 51°2'42.939" N 9°17'8.79" E