The calculated distance (air line) between Mostaganem and Assi Bou Nif is approximately 37 miles respectively 59 kilometers.
By car or train, the actual journey to Assi Bou Nif is certainly longer, as only the direct route (as the crow flies) between Mostaganem and Assi Bou Nif has been calculated here.
Air line (approximately)
59 kilometers
32 nautical miles