The calculated distance (air line) between Sinanju and Sariwŏn-si is approximately 76 miles respectively 122 kilometers.
By car or train, the actual journey to Sariwŏn-si is certainly longer, as only the direct route (as the crow flies) between Sinanju and Sariwŏn-si has been calculated here.
Air line (approximately)
122 kilometers
66 nautical miles