The calculated distance (air line) between Yŏnan-ŭp and Tŏkch’ŏn is approximately 128 miles respectively 205 kilometers.
By car or train, the actual journey to Tŏkch’ŏn is certainly longer, as only the direct route (as the crow flies) between Yŏnan-ŭp and Tŏkch’ŏn has been calculated here.