The calculated distance (air line) between Sŭngho 1-tong and Hongwŏn is approximately 127 miles respectively 205 kilometers.
By car or train, the actual journey to Hongwŏn is certainly longer, as only the direct route (as the crow flies) between Sŭngho 1-tong and Hongwŏn has been calculated here.
Air line (approximately)
205 kilometers
111 nautical miles