The calculated distance (air line) between Gros Islet and Rivière-Pilote is approximately 29 miles respectively 47 kilometers.
By car or train, the actual journey to Rivière-Pilote is certainly longer, as only the direct route (as the crow flies) between Gros Islet and Rivière-Pilote has been calculated here.
Air line (approximately)
47 kilometers
25 nautical miles