The calculated distance (air line) between Uijeongbu-si and Wŏnsan is approximately 100 miles respectively 161 kilometers.
By car or train, the actual journey to Wŏnsan is certainly longer, as only the direct route (as the crow flies) between Uijeongbu-si and Wŏnsan has been calculated here.
Air line (approximately)
161 kilometers
87 nautical miles