The calculated distance (air line) between Ungsang-nodongjagu and Slavyanka is approximately 59 miles respectively 94 kilometers.
By car or train, the actual journey to Slavyanka is certainly longer, as only the direct route (as the crow flies) between Ungsang-nodongjagu and Slavyanka has been calculated here.
Air line (approximately)
94 kilometers
51 nautical miles