The calculated distance (air line) between Bochum-Hordel and Saarbrücken is approximately 157 miles respectively 253 kilometers.
By car or train, the actual journey to Saarbrücken is certainly longer, as only the direct route (as the crow flies) between Bochum-Hordel and Saarbrücken has been calculated here.
Air line (approximately)
253 kilometers
136 nautical miles