The calculated distance (air line) between Mejdan - Obilićevo and Gradiška is approximately 27 miles respectively 43 kilometers.
By car or train, the actual journey to Gradiška is certainly longer, as only the direct route (as the crow flies) between Mejdan - Obilićevo and Gradiška has been calculated here.
Air line (approximately)
43 kilometers
23 nautical miles