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