The calculated distance (air line) between Bonn and Sint-Kwintens-Lennik is approximately 129 miles respectively 207 kilometers.
By car or train, the actual journey to Sint-Kwintens-Lennik is certainly longer, as only the direct route (as the crow flies) between Bonn and Sint-Kwintens-Lennik has been calculated here.
Air line (approximately)
207 kilometers
112 nautical miles