The calculated distance (air line) between Pohang and Yangp'yŏng is approximately 145 miles respectively 233 kilometers.
By car or train, the actual journey to Yangp'yŏng is certainly longer, as only the direct route (as the crow flies) between Pohang and Yangp'yŏng has been calculated here.
Air line (approximately)
233 kilometers
126 nautical miles