The calculated distance (air line) between Arrasate / Mondragón and Zarautz is approximately 22 miles respectively 36 kilometers.
By car or train, the actual journey to Zarautz is certainly longer, as only the direct route (as the crow flies) between Arrasate / Mondragón and Zarautz has been calculated here.
Air line (approximately)
36 kilometers
19 nautical miles