The calculated distance (air line) between Saint-Leu-la-Forêt and Amiens is approximately 61 miles respectively 98 kilometers.
By car or train, the actual journey to Amiens is certainly longer, as only the direct route (as the crow flies) between Saint-Leu-la-Forêt and Amiens has been calculated here.
Air line (approximately)
98 kilometers
53 nautical miles