Basajaun is a fixed-route ultra-distance event run by the Transiberica Randonneurs Cycling Club, starting in Vitoria-Gasteiz. It is not competitive and, according to the organiser, 70% of the route is off tarmac.
The 2027 edition is announced for 25 July. In 2026 it was 890 km and about 15,000 m of climbing, from 26 to 31 July. The track is given to entrants a few weeks before the start.