The calculated distance (air line) between As Sulaymānīyah and Sīnah is approximately 159 miles respectively 255 kilometers.
By car or train, the actual journey to Sīnah is certainly longer, as only the direct route (as the crow flies) between As Sulaymānīyah and Sīnah has been calculated here.
Air line (approximately)
255 kilometers
138 nautical miles