The calculated distance (air line) between Bochum and Montignies-sur-Sambre is approximately 140 miles respectively 225 kilometers.
By car or train, the actual journey to Montignies-sur-Sambre is certainly longer, as only the direct route (as the crow flies) between Bochum and Montignies-sur-Sambre has been calculated here.
Air line (approximately)
225 kilometers
121 nautical miles