The calculated distance (air line) between Saint-Louis and Piton Saint-Leu is approximately 8 miles respectively 12 kilometers.
By car or train, the actual journey to Piton Saint-Leu is certainly longer, as only the direct route (as the crow flies) between Saint-Louis and Piton Saint-Leu has been calculated here.
Air line (approximately)
12 kilometers
7 nautical miles