The calculated distance (air line) between As Sulaymānīyah and Ḩalabja is approximately 41 miles respectively 66 kilometers.
By car or train, the actual journey to Ḩalabja is certainly longer, as only the direct route (as the crow flies) between As Sulaymānīyah and Ḩalabja has been calculated here.
Air line (approximately)
66 kilometers
36 nautical miles