The calculated distance (air line) between Wŏnju and Gyeongsan-si is approximately 114 miles respectively 184 kilometers.
By car or train, the actual journey to Gyeongsan-si is certainly longer, as only the direct route (as the crow flies) between Wŏnju and Gyeongsan-si has been calculated here.
Air line (approximately)
184 kilometers
99 nautical miles