The calculated distance (air line) between Neufchâteau and Sint-Niklaas is approximately 108 miles respectively 173 kilometers.
By car or train, the actual journey to Sint-Niklaas is certainly longer, as only the direct route (as the crow flies) between Neufchâteau and Sint-Niklaas has been calculated here.
Air line (approximately)
173 kilometers
94 nautical miles