The calculated distance (air line) between Bellegarde-sur-Valserine and Nîmes is approximately 173 miles respectively 278 kilometers.
By car or train, the actual journey to Nîmes is certainly longer, as only the direct route (as the crow flies) between Bellegarde-sur-Valserine and Nîmes has been calculated here.
Air line (approximately)
278 kilometers
150 nautical miles