The calculated distance (air line) between Santutxu and Aretxabaleta is approximately 26 miles respectively 41 kilometers.
By car or train, the actual journey to Aretxabaleta is certainly longer, as only the direct route (as the crow flies) between Santutxu and Aretxabaleta has been calculated here.
Air line (approximately)
41 kilometers
22 nautical miles