95 km
5 h
600 m

1- Parking
2- 3- 4- Senda
5- La Viñeta
6- S. Martín de la Val d’ Onsera
7- Senda de los Burros
8- 9- senda
10- Parking

1-Past San Julián de Banzo, a detour to the right, signposted, will put us on the track that goes to the parking. From here, we will take the path that descends to the ravine.
2- Once inside the ravine, we will go up its channel on remains of gravel. There is a small detour to the left signposted with a landmark, which first ascends on the riverbed and then returns to it. (optional)
3 – The walls are narrowing and the channel zigzags until our first detour. The path goes to the right, signposted with a great landmark, ascends by a stream and a forest, to reach a strained wall (climbing area). Soon after there is a crossing of paths, we will take the one that goes to the left. The other one will be used in the descent.
4- Now the path winds and ascends vertiginously among trees and bushes, until it brings us closer to the wall. Painted, a plaque and a signposted detour will confirm that we are on the right track.
5- We will take the path on the left (La Viñeta) that will take us up to the pass. A handrail and handrails will facilitate the ascent. After the path is little marked but the evidence of the hill leaves no doubt.
6 – Once up, in the pass, we will descend to the ravine by a path that goes out to our left, when we reach the channel we will turn to the right and we will go back to the hermitage.
7- Back on our steps we will return to the pass. As we arrive at the top, we will turn left in the direction of San Julián de Banzo- Llanos de Ciano along Senda los Burros.
8- On this path we will go down to the crossroads where the graffiti and the plaque were. Few meters after passing the graffiti, there is a little defined path to the left, which enters a forest, where red paintings on the trunks will lead us to the bottom of the ravine
9-From here, a well marked path on a pedriza and half hillside, will leave us at a crossroads, in which we turn to the right (signposted) going down quickly to the crossroads where was the climbing area described above.
10- Now we just have to return by the path, the channel of the ravine and ascend to the parking lot, undoing our first steps of the route

History and  culture
Not far from San Julián, to the south of the Matapaños, at the base of some rocks that attract by their appearance and in the deepest part of a ravine reached by an opening so narrow that it does not let two men in front, there is a hermitage in honor of San Martín, Bishop of Tours. I’m sorry I did not have time to go see that chapel located in a place full of mystery. In addition, we must leave the opportunity to explore and describe those to whom we are now pointing the way. (Text taken from “excursions by Aragón and Navarra 1882”) SAINT-SAUD As soon as we start, we will descend to enter the San Martín ravine. Between bojes, moss, bear ears, some wild strawberry and blackberries we will ascend through the bed of engraving and surrounded by limestone rocks. Normally the channel is dry, but underground water runs underground, which appear and disappear mysteriously. In small plain false we will find a very interesting commemorative plaque. Now the pines and holm oaks are mixed with the previous vegetation. Some stairs and ropes, as if it were a via ferrata, facilitate access to hikers and pilgrims. Already at the top of the hill the aroma of savory impregnates the environment and the limestone gives way to the impressive masses of conglomerate. On the left, the walls close almost completely, as if one will lie on top of the other. This part is well known to canyons. On the right a circus, shows us where the hermitage is. We will have special attention when we are inside the ravine, because its walls are inhabited by griffon vultures, lammergeyers, Egyptian vultures, choughs and pigeons, which, as they alight and take off, can shed rocks on us. We will also be careful not to step on the tritons that live in the stream that we will have to cross, using the stones, so as not to get wet. The rock church of San Martin, according to some authors, could have Visigoth origins, but the reality is that the first documents that name it are from 1075. It served as a monastery and in 1572 it passed into the hands of hermits remaining in good condition. In the civil war it was sacked, which was quite deteriorated over the years and the punishment of war. After a laborious restoration work has recovered part of its splendor.