The calculated distance (air line) between Grevenbroich and Niederkrüchten is approximately 18 miles respectively 28 kilometers.
By car or train, the actual journey to Niederkrüchten is certainly longer, as only the direct route (as the crow flies) between Grevenbroich and Niederkrüchten has been calculated here.
Air line (approximately)
28 kilometers
15 nautical miles