The calculated distance (air line) between Hwangju-ŭp and Manp’o is approximately 174 miles respectively 280 kilometers.
By car or train, the actual journey to Manp’o is certainly longer, as only the direct route (as the crow flies) between Hwangju-ŭp and Manp’o has been calculated here.
Air line (approximately)
280 kilometers
151 nautical miles