This route approaches Aizkorri Range from the NW. Once reached the Urbia Meseta it ascends to Arbelaitz, the northern most peak of the ‘sierra’ over the 1.500 meters, it follows the SE-bearing ridge till Aizkorri mountain, passing all the tops with more than 1.500 meters. The journey continues descending over the south slopes of Aizkorri to the San Adrian pass and, finally, it returns to the Monastery of Aranzazu crossing the whole meseta of Urbia.
It takes about 8 hours (normal rhythm) including pauses, and approximately 6 hours without stopping. The initial climb from the Monastery of Aranzazu till the top of Aketegi (1.544 m) is 820 heigth-meters, but the total ascend of the excursion exceeds 1600 heigh-meters. The whole route has about 21 km.
The journey begins at the Monastery of Aranzazu (725 m), in the middle of the Basque Mountains. The Monastery can be reached from the village of Oñati, 9 km over a narrow asphalt road to the north. There are no regular bus connections between Oñati and Aranzazu, so the distance has to be done with a taxi from the village.
Oñati is very well connected with Bilbao thanks to a direct system of buses which depart from Bilbao’s General Bus Station (next to the football stadium). These buses depart at 14:30 hrs and at 20:30 every working day and Saturdays, and at 21:00 hrs on Sundays and holidays.
Bilbao has an International Airport (Sondica). Buses connect the airport with the city centre.
We begin to walk at the Monastery of Aranzazu. An asphalted road goes behind the church and crosses the small village. After 5 minutes the paved road becomes a dusty road. There is a place for parking to the left. At this same place there is a split to the right and down, and to the left and up. We go up over the unpaved road. After some hundreds meters we reach another parking place. There is a iron gate to the left which closes the pass to motor vehicles to the mountain. We walk in to this road that ascends through a pine forest.
We will leave a water spring to the left (and a little bit away from the, still, unpaved road). Some minutes further the road becomes a narrow mountain path and continues going up through the forest of pines mixed with beech trees. Progressively these beech trees will substitute the pines. After 50 minutes walking we will reach the pass of Eloa (1.160 m), where a post marks the ways. To our right the rocky summit of Zabalaitz (1.251 m), and some minutes descending by a lane with a line of trees at each side we reach the a church and, later, a house of Urbia. In front of the entrance of the house there is a water spring.
From this point we walk on the plane meseta bearing to a very prominent peak to the west: the Arbelaitz (1.525 m), our first target on the ridge of Azkorri. We follow a wide track (dusty road) that we will leave when we reach the first of a row of small stones standing up and marking the way up to the mountain. This row of marks starts from the dusty road itself at the point where it makes a clear bending to the right. We will follow this marks that bring us up the hill over the most treeless slopes of the mountain. There will be a forest to the right and another forest in a small gully to the left, but we ascend directly over the steep slope and the summit will be gained after half hour from the first mark, down next to the road.
To the SE the whole ridge of Azkorri with all its summits. After Arbelaitz (mentioned above),Iraule (1.526 m) will follow. It is reached after 25 minutes walking over the rocky ridge (with a small scramble here and there this is the most difficult part of the whole traverse). The highest point of the province, Aitxuri (1.551 m), is next. Then comes the most impressive top seen from Arbelaitz: Aketegi, with 1.544 m is . Half hour walking on the ridge is enough to stand on its top. The most we walk to the SE the easier the terrain becomes. Finally, we arrive at Aizkorri itself (1.531 m).
The descend will follow the ascending route described here as “Otzaurte-San Adrian”. It passes the step-crossing of Aiztontor Altua, where, with hard snow or ice (caused by many people stepping the snow) can be tricky (surely descending) and ice axe and crampons (or being very careful) is advisable. If dry, it will not be a problem.
The path descends through a dense beech trees’ forest and reaches a meadow to the right (in descend). From this point we could walk to the left a pair of hundred meters over the old Roman road till the bizarre “Paso de San Adrian”. Then, we would have to walk back to the meadow at the exit of the forest to continue the route here proposed to Aranzazu.
The way back to the Monastery of Aranzazu requires to go to the right when coming out from the forest. The Roman road goes up (S bearing) and makes a bending to the right some meters further away from the meadow. The Roman road has to be followed till a second bending to the left, where the road continues ascending. At this point (about 250 m on the R. road) there is a small (difficult to see) path to the right that leaves the road. Till this time there are two small mountains of stones marking the point where we have to enter this path which walks into a forest.
This beautiful way through the forest will ascend till a pass and, then continue on more open terrain. Here is easy to get lost, especially with fog (common in this meseta surrounded by mountain ranges). Despite a clear network of signs, with white and red paint, we will have to be concentrated in track-finding. A compass and map can be very useful.
Eventually a second forest is passed and then, some lonely mountain houses are visible to the right. Further away we will reach the shepherds’ settlement of “Peru Saroi” (1.148 m). From this point the way back to the plains of Urbia is much more obvious.
The Ridge Traverse of the Aizkorri Range needs a good pair of mountain boots, and some food and water supplies in the backpack. Warm clothes, even in summer, are not a bad idea.
In winter crampons and an ice axe can be very useful to progress safely up on the ridge with hard snow or, even ice (stepped snow). Rope and climbing material are not necessary. With snow sunglasses should be worn. Extra clothing (gloves, gaiters, etc…) are very much recommended.
Compass (or GPS) and a good map is highly recommended to cross the Urbia meseta, surely with foggy weather.