The calculated distance (air line) between Namp’o and P’yŏngsŏng is approximately 43 miles respectively 69 kilometers.
By car or train, the actual journey to P’yŏngsŏng is certainly longer, as only the direct route (as the crow flies) between Namp’o and P’yŏngsŏng has been calculated here.
Air line (approximately)
69 kilometers
37 nautical miles