The calculated distance (air line) between Yŏch’im-dong and Namp’o is approximately 131 miles respectively 210 kilometers.
By car or train, the actual journey to Namp’o is certainly longer, as only the direct route (as the crow flies) between Yŏch’im-dong and Namp’o has been calculated here.
Air line (approximately)
210 kilometers
113 nautical miles