The calculated distance (air line) between Basrah and Ar Rumaythīyah is approximately 85 miles respectively 136 kilometers.
By car or train, the actual journey to Ar Rumaythīyah is certainly longer, as only the direct route (as the crow flies) between Basrah and Ar Rumaythīyah has been calculated here.
Air line (approximately)
136 kilometers
73 nautical miles