The calculated distance (air line) between Ardatov and Nizhniy Novgorod is approximately 83 miles respectively 134 kilometers.
By car or train, the actual journey to Nizhniy Novgorod is certainly longer, as only the direct route (as the crow flies) between Ardatov and Nizhniy Novgorod has been calculated here.
Air line (approximately)
134 kilometers
72 nautical miles