The calculated distance (air line) between Amiens and Saint-Pol-sur-Ternoise is approximately 33 miles respectively 54 kilometers.
By car or train, the actual journey to Saint-Pol-sur-Ternoise is certainly longer, as only the direct route (as the crow flies) between Amiens and Saint-Pol-sur-Ternoise has been calculated here.
Air line (approximately)
54 kilometers
29 nautical miles