The calculated distance (air line) between Herstal and Woluwe-Saint-Lambert is approximately 54 miles respectively 86 kilometers.
By car or train, the actual journey to Woluwe-Saint-Lambert is certainly longer, as only the direct route (as the crow flies) between Herstal and Woluwe-Saint-Lambert has been calculated here.
Air line (approximately)
86 kilometers
47 nautical miles