The calculated distance (air line) between Bochum-Hordel and Hildesheim is approximately 127 miles respectively 204 kilometers.
By car or train, the actual journey to Hildesheim is certainly longer, as only the direct route (as the crow flies) between Bochum-Hordel and Hildesheim has been calculated here.
Air line (approximately)
204 kilometers
110 nautical miles