The calculated distance (air line) between Mechelen-aan-de-Maas and Tournai is approximately 104 miles respectively 167 kilometers.
By car or train, the actual journey to Tournai is certainly longer, as only the direct route (as the crow flies) between Mechelen-aan-de-Maas and Tournai has been calculated here.
Air line (approximately)
167 kilometers
90 nautical miles