The calculated distance (air line) between Mongar and Wangdue Phodrang is approximately 84 miles respectively 134 kilometers.
By car or train, the actual journey to Wangdue Phodrang is certainly longer, as only the direct route (as the crow flies) between Mongar and Wangdue Phodrang has been calculated here.
Air line (approximately)
134 kilometers
73 nautical miles