The calculated distance (air line) between Oer-Erkenschwick and Gelsenkirchen is approximately 12 miles respectively 19 kilometers.
By car or train, the actual journey to Gelsenkirchen is certainly longer, as only the direct route (as the crow flies) between Oer-Erkenschwick and Gelsenkirchen has been calculated here.
Air line (approximately)
19 kilometers
10 nautical miles