The calculated distance (air line) between Yŏnggwang-ŭp and Sil-li is approximately 111 miles respectively 179 kilometers.
By car or train, the actual journey to Sil-li is certainly longer, as only the direct route (as the crow flies) between Yŏnggwang-ŭp and Sil-li has been calculated here.
Air line (approximately)
179 kilometers
97 nautical miles