The calculated distance (air line) between Pukchil-lodongjagu and Hŭngnam is approximately 103 miles respectively 165 kilometers.
By car or train, the actual journey to Hŭngnam is certainly longer, as only the direct route (as the crow flies) between Pukchil-lodongjagu and Hŭngnam has been calculated here.
Air line (approximately)
165 kilometers
89 nautical miles