The calculated distance (air line) between Strelka and Rostov-na-Donu is approximately 182 miles respectively 293 kilometers.
By car or train, the actual journey to Rostov-na-Donu is certainly longer, as only the direct route (as the crow flies) between Strelka and Rostov-na-Donu has been calculated here.
Air line (approximately)
293 kilometers
158 nautical miles