The calculated distance (air line) between Kowŏn-ŭp and Ŭnch’ŏn-ŭp is approximately 115 miles respectively 184 kilometers.
By car or train, the actual journey to Ŭnch’ŏn-ŭp is certainly longer, as only the direct route (as the crow flies) between Kowŏn-ŭp and Ŭnch’ŏn-ŭp has been calculated here.
Air line (approximately)
184 kilometers
100 nautical miles