The calculated distance (air line) between Rheda-Wiedenbrück and Gelsenkirchen is approximately 57 miles respectively 91 kilometers.
By car or train, the actual journey to Gelsenkirchen is certainly longer, as only the direct route (as the crow flies) between Rheda-Wiedenbrück and Gelsenkirchen has been calculated here.
Air line (approximately)
91 kilometers
49 nautical miles