The calculated distance (air line) between Staromyshastovskaya and Krasnodar is approximately 21 miles respectively 34 kilometers.
By car or train, the actual journey to Krasnodar is certainly longer, as only the direct route (as the crow flies) between Staromyshastovskaya and Krasnodar has been calculated here.
Air line (approximately)
34 kilometers
18 nautical miles