The calculated distance (air line) between Mennzel Bou Zelfa and Nabeul is approximately 18 miles respectively 29 kilometers.
By car or train, the actual journey to Nabeul is certainly longer, as only the direct route (as the crow flies) between Mennzel Bou Zelfa and Nabeul has been calculated here.
Air line (approximately)
29 kilometers
16 nautical miles