The calculated distance (air line) between Fereydūnshahr and Shūshtar is approximately 96 miles respectively 155 kilometers.
By car or train, the actual journey to Shūshtar is certainly longer, as only the direct route (as the crow flies) between Fereydūnshahr and Shūshtar has been calculated here.
Air line (approximately)
155 kilometers
84 nautical miles