The calculated distance (air line) between Saint-Maximin-la-Sainte-Baume and Montpellier is approximately 100 miles respectively 161 kilometers.
By car or train, the actual journey to Montpellier is certainly longer, as only the direct route (as the crow flies) between Saint-Maximin-la-Sainte-Baume and Montpellier has been calculated here.
Air line (approximately)
161 kilometers
87 nautical miles