The calculated distance (air line) between Laudun-l'Ardoise and Saint-Étienne is approximately 93 miles respectively 149 kilometers.
By car or train, the actual journey to Saint-Étienne is certainly longer, as only the direct route (as the crow flies) between Laudun-l'Ardoise and Saint-Étienne has been calculated here.
Air line (approximately)
149 kilometers
81 nautical miles