The calculated distance (air line) between Gehrden and Bochum-Hordel is approximately 118 miles respectively 189 kilometers.
By car or train, the actual journey to Bochum-Hordel is certainly longer, as only the direct route (as the crow flies) between Gehrden and Bochum-Hordel has been calculated here.
Air line (approximately)
189 kilometers
102 nautical miles