The calculated distance (air line) between Kujang-ŭp and Songnim-ni is approximately 79 miles respectively 127 kilometers.
By car or train, the actual journey to Songnim-ni is certainly longer, as only the direct route (as the crow flies) between Kujang-ŭp and Songnim-ni has been calculated here.
Air line (approximately)
127 kilometers
69 nautical miles