The calculated distance (air line) between Iwŏn-ŭp and Sŭngho 1-tong is approximately 170 miles respectively 273 kilometers.
By car or train, the actual journey to Sŭngho 1-tong is certainly longer, as only the direct route (as the crow flies) between Iwŏn-ŭp and Sŭngho 1-tong has been calculated here.
Air line (approximately)
273 kilometers
147 nautical miles