The calculated distance (air line) between Saint-Roch-de-l'Achigan and Nepean is approximately 109 miles respectively 176 kilometers.
By car or train, the actual journey to Nepean is certainly longer, as only the direct route (as the crow flies) between Saint-Roch-de-l'Achigan and Nepean has been calculated here.
Air line (approximately)
176 kilometers
95 nautical miles