The calculated distance (air line) between Madīnat an Naşr and Ḩalwān is approximately 16 miles respectively 25 kilometers.
By car or train, the actual journey to Ḩalwān is certainly longer, as only the direct route (as the crow flies) between Madīnat an Naşr and Ḩalwān has been calculated here.
Air line (approximately)
25 kilometers
14 nautical miles