The calculated distance (air line) between Arrasate / Mondragón and Lekeitio is approximately 21 miles respectively 33 kilometers.
By car or train, the actual journey to Lekeitio is certainly longer, as only the direct route (as the crow flies) between Arrasate / Mondragón and Lekeitio has been calculated here.
Air line (approximately)
33 kilometers
18 nautical miles