The calculated distance (air line) between Bochum-Hordel and Sint-Michiels is approximately 172 miles respectively 278 kilometers.
By car or train, the actual journey to Sint-Michiels is certainly longer, as only the direct route (as the crow flies) between Bochum-Hordel and Sint-Michiels has been calculated here.
Air line (approximately)
278 kilometers
150 nautical miles