The calculated distance (air line) between Ars-sur-Moselle and Liverdun is approximately 23 miles respectively 37 kilometers.
By car or train, the actual journey to Liverdun is certainly longer, as only the direct route (as the crow flies) between Ars-sur-Moselle and Liverdun has been calculated here.
Air line (approximately)
37 kilometers
20 nautical miles