The calculated distance (air line) between Arlon and Molenbeek-Saint-Jean is approximately 104 miles respectively 168 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 Arlon and Molenbeek-Saint-Jean has been calculated here.
Air line (approximately)
168 kilometers
91 nautical miles