The calculated distance (air line) between Besançon and La Chaux-de-Fonds is approximately 39 miles respectively 63 kilometers.
By car or train, the actual journey to La Chaux-de-Fonds is certainly longer, as only the direct route (as the crow flies) between Besançon and La Chaux-de-Fonds has been calculated here.
Air line (approximately)
63 kilometers
34 nautical miles