The calculated distance (air line) between Champagne-au-Mont-d'Or and Aix-en-Provence is approximately 160 miles respectively 257 kilometers.
By car or train, the actual journey to Aix-en-Provence is certainly longer, as only the direct route (as the crow flies) between Champagne-au-Mont-d'Or and Aix-en-Provence has been calculated here.
Air line (approximately)
257 kilometers
139 nautical miles