In the village of Ascain, park in the car park by the Roman bridge.
(S/E) Cross the bridge over the stream next to the car park and continue north-east along the ascending road, Route d’Errotenea. Follow it until you reach a right-angle bend and turn right. Then take thethird street on the left onto Chemin de Karrika Zaharra. Follow it until you reach a junction with the Chemin de Martikonea. Turn right and, about a hundred metres further on, you’ll come to the start of a footpath on your right.
(1) Continue along this path and cross the stream called Uzkaingo Erreka twice.
(2) Cross the stream again. Follow the path as it winds alongside the stream, cross it again a little further on, then continue uphill. Pass a path junction on the left and you’ll soon reach a crossroads.
(3) Turn left towards Birkatzun. Once at the summit, carry on straight ahead along the path that leads down.
(4) Turn off onto the path on the left towards Martinhaurrenborda farm, a building made of cut stone. Continue to the left for about a hundred metres, then turn right onto a wide path which, further on, makes a 90° bend to the right.
(5) Immediately afterwards, turn 180° to the left onto a path that runs alongside a fenced-off field. Continue to a junction.
(6) Carry on to the left. The path crosses the Uzkaingo Erreka stream, then bends to the left to run alongside it. Make sure you keep heading in the same direction, as close to the stream as possible.
(7) Turn left and continue alongside the stream, crossing it twice more before rejoining the original path.
(2) Turn left onto the path, heading in the opposite direction to the way out, and make your way back to the car park by crossing the Errotenea housing estate (S/E).