The calculated distance (air line) between Palermo and Castellammare del Golfo is approximately 27 miles respectively 43 kilometers.
By car or train, the actual journey to Castellammare del Golfo is certainly longer, as only the direct route (as the crow flies) between Palermo and Castellammare del Golfo has been calculated here.
Air line (approximately)
43 kilometers
23 nautical miles