The calculated distance (air line) between La Roque-d'Anthéron and Marseille is approximately 29 miles respectively 47 kilometers.
By car or train, the actual journey to Marseille is certainly longer, as only the direct route (as the crow flies) between La Roque-d'Anthéron and Marseille has been calculated here.
Air line (approximately)
47 kilometers
25 nautical miles