The calculated distance (air line) between Welkenraedt and Molenbeek-Saint-Jean is approximately 74 miles respectively 119 kilometers.
By car or train, the actual journey to Molenbeek-Saint-Jean is certainly longer, as only the direct route (as the crow flies) between Welkenraedt and Molenbeek-Saint-Jean has been calculated here.
Air line (approximately)
119 kilometers
64 nautical miles