The calculated distance (air line) between Gwangmyeong and Hongch’ŏn is approximately 58 miles respectively 93 kilometers.
By car or train, the actual journey to Hongch’ŏn is certainly longer, as only the direct route (as the crow flies) between Gwangmyeong and Hongch’ŏn has been calculated here.
Air line (approximately)
93 kilometers
50 nautical miles