The calculated distance (air line) between Hyesan-dong and Sinsang-ni is approximately 127 miles respectively 205 kilometers.
By car or train, the actual journey to Sinsang-ni is certainly longer, as only the direct route (as the crow flies) between Hyesan-dong and Sinsang-ni has been calculated here.
Air line (approximately)
205 kilometers
111 nautical miles