The calculated distance (air line) between Bela Crkva and Sremska Mitrovica is approximately 88 miles respectively 142 kilometers.
By car or train, the actual journey to Sremska Mitrovica is certainly longer, as only the direct route (as the crow flies) between Bela Crkva and Sremska Mitrovica has been calculated here.
Air line (approximately)
142 kilometers
77 nautical miles