The calculated distance (air line) between Rostov-na-Donu and Kuybyshevo is approximately 55 miles respectively 89 kilometers.
By car or train, the actual journey to Kuybyshevo is certainly longer, as only the direct route (as the crow flies) between Rostov-na-Donu and Kuybyshevo has been calculated here.
Air line (approximately)
89 kilometers
48 nautical miles