The calculated distance (air line) between Yŏnggwang-ŭp and Hŭngnam is approximately 15 miles respectively 25 kilometers.
By car or train, the actual journey to Hŭngnam is certainly longer, as only the direct route (as the crow flies) between Yŏnggwang-ŭp and Hŭngnam has been calculated here.
Air line (approximately)
25 kilometers
13 nautical miles