The calculated distance (air line) between Muang Phônsavan and Xam Nua is approximately 87 miles respectively 140 kilometers.
By car or train, the actual journey to Xam Nua is certainly longer, as only the direct route (as the crow flies) between Muang Phônsavan and Xam Nua has been calculated here.
Air line (approximately)
140 kilometers
75 nautical miles