The calculated distance (air line) between Saint-Mitre-les-Remparts and Saint-Étienne is approximately 140 miles respectively 226 kilometers.
By car or train, the actual journey to Saint-Étienne is certainly longer, as only the direct route (as the crow flies) between Saint-Mitre-les-Remparts and Saint-Étienne has been calculated here.
Air line (approximately)
226 kilometers
122 nautical miles