The calculated distance (air line) between Yŏnggwang-ŭp and Hoeyang is approximately 91 miles respectively 146 kilometers.
By car or train, the actual journey to Hoeyang is certainly longer, as only the direct route (as the crow flies) between Yŏnggwang-ŭp and Hoeyang has been calculated here.
Air line (approximately)
146 kilometers
79 nautical miles