The calculated distance (air line) between Taesal-li and Pyeongtaek is approximately 35 miles respectively 56 kilometers.
By car or train, the actual journey to Pyeongtaek is certainly longer, as only the direct route (as the crow flies) between Taesal-li and Pyeongtaek has been calculated here.
Air line (approximately)
56 kilometers
30 nautical miles