The calculated distance (air line) between Poisy and Aix-en-Provence is approximately 168 miles respectively 270 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 Poisy and Aix-en-Provence has been calculated here.
Air line (approximately)
270 kilometers
146 nautical miles