The calculated distance (air line) between Seeheim-Jugenheim and Gelsenkirchen is approximately 138 miles respectively 222 kilometers.
By car or train, the actual journey to Gelsenkirchen is certainly longer, as only the direct route (as the crow flies) between Seeheim-Jugenheim and Gelsenkirchen has been calculated here.
Air line (approximately)
222 kilometers
120 nautical miles