The calculated distance (air line) between Pyeongtaek and Hongch’ŏn is approximately 65 miles respectively 105 kilometers.
By car or train, the actual journey to Hongch’ŏn is certainly longer, as only the direct route (as the crow flies) between Pyeongtaek and Hongch’ŏn has been calculated here.
Air line (approximately)
105 kilometers
57 nautical miles