The calculated distance (air line) between Unión Chocó and Nuevo Arraiján is approximately 160 miles respectively 258 kilometers.
By car or train, the actual journey to Nuevo Arraiján is certainly longer, as only the direct route (as the crow flies) between Unión Chocó and Nuevo Arraiján has been calculated here.
Air line (approximately)
258 kilometers
139 nautical miles