From the Behobie border (near Irun) take the N-121-A to Doneztebe/Santesteban.
From there, follow the NA-170 past Elgorriaga and Ituren to Auritz (or Aurtitz).
Park in the small square beside the road.
(S/E) Follow North-West along the street parallel to the road, where the red/white signs start.
(1) At the crossroads, leave the road and take the gravel path up to the left (signs).
(2) At the crossroads, at the water main, turn left onto the wide track marked Red/White. Further on, the track crosses a stream, with a small waterfall on the right.
(3) A hundred metres further on, turn right following the signs. Pass a beautiful sheep pen and follow the signs, forking right. The path rises into the forest, skirting the stream.
(4) At the track, keep left. A few metres after a sharp left-hand bend, you'll find a trailhead on the right. Follow it uphill along the stream, past a stone bridge which you must not cross, to reach the Mendaur dam.
(5) At the dam, continue uphill and at the crow's feet, turn right towards the end of the lake.
(6) At an attractive picnic area, cross the feeder stream and follow the path to the right. The path, still signposted, soon rises steeply.
(7) Reach the Mendaur Pass and its menhir. To the right, take the path that winds up to the summit topped by the hermitage (Ermita de la Trinidad). If you walk at a leisurely pace, it will take you 1/2 hour to reach the summit.
(8) After visiting the building and admiring the view, return along the same route to the dam.
(5) Along the wall bordering the lake, don't go down the outward path, but continue on the track that runs horizontally due South. Follow this track as it winds its way up to the village (S/E).