The calculated distance (air line) between Yeongdong and Gwangmyeong is approximately 103 miles respectively 166 kilometers.
By car or train, the actual journey to Gwangmyeong is certainly longer, as only the direct route (as the crow flies) between Yeongdong and Gwangmyeong has been calculated here.
Air line (approximately)
166 kilometers
90 nautical miles