The calculated distance (air line) between Nakhon Phanom and Ban Selaphum is approximately 111 miles respectively 178 kilometers.
By car or train, the actual journey to Ban Selaphum is certainly longer, as only the direct route (as the crow flies) between Nakhon Phanom and Ban Selaphum has been calculated here.
Air line (approximately)
178 kilometers
96 nautical miles