The calculated distance (air line) between Aix-en-Provence and Marseille 16 is approximately 13 miles respectively 21 kilometers.
By car or train, the actual journey to Marseille 16 is certainly longer, as only the direct route (as the crow flies) between Aix-en-Provence and Marseille 16 has been calculated here.
Air line (approximately)
21 kilometers
11 nautical miles