From the Wikipedia page [1]
Gelnhausen is a town and the capital of the Main-Kinzig-Kreis, in Hesse, Germany. It is located approximately 40 kilometers east of Frankfurt am Main, between the Vogelsberg mountains and the Spessart range at the river Kinzig. It is one of the eleven towns (urban municipalities) in the district. Gelnhausen has around 22,000 inhabitants.