The calculated distance (air line) between Hoeyang and Yangp'yŏng is approximately 85 miles respectively 136 kilometers.
By car or train, the actual journey to Yangp'yŏng is certainly longer, as only the direct route (as the crow flies) between Hoeyang and Yangp'yŏng has been calculated here.
Air line (approximately)
136 kilometers
73 nautical miles