The calculated distance (air line) between Dien Bien Phu and Vĩnh Yên is approximately 166 miles respectively 268 kilometers.
By car or train, the actual journey to Vĩnh Yên is certainly longer, as only the direct route (as the crow flies) between Dien Bien Phu and Vĩnh Yên has been calculated here.
Air line (approximately)
268 kilometers
144 nautical miles