Starting at the Encamp tourist office and finishing at the Canillo tourist office, this is a very demanding route. We advise against doing it unless there is a very favourable weather forecast, because fog or heavy rainfall could cause serious problems. Keep in mind that the terrain in many sections is complicated and, although it can be followed easily with GPS, with poor visibility it will be very slow going. Practically the entire route has markings to guide you, first the yellow dots of the CC (communal path), then red and white GR markings, then the red and yellow GRP markings and finally, in the last 7 km, those of the mountain biking route and yellow too.

In addition to the safety equipment that is essential on high-mountain routes, we recommend that you bring a mini water purifier and water purification tablets to safely fill your hydration bag. Be especially careful as from Estany Primer de Pessons you will not find water until you almost reach Canillo where, with 3 km to go, there is a stream that crosses the path that usually carries very fresh water.

Leave through the streets of Encamp until you cross the road, where you will find two sets of stairs, the one you want is the one on the left. From here the path first goes through the forest, you will cross an area of boulders where you have to go left, sticking to the wall,  even though the GPS may tell you that the route is through the middle of the boulders. A long climb takes you to the Agols shelter, which is an open and unstaffed refuge, where the spring there usually provides very good water (not potable). Leaving the shelter behind, you will soon notice that the track leaves the path and heads right towards the pass near Cap dels Agols. This section is not paved at all and you will have to look for the best path between the bushes and rocks. It is a short section with no added difficulty other than the orientation of going upwards as straight as possible. Once you have reached the Coll dels Agols, the path to the end of the route is well paved and will present few doubts. From the pass, descend to the Estany Blau, skirt around it and continue on a steep descent until you find the GR-11 at the bottom of the Madriu River valley, which you will not leave until you reach Refugi de l'Illa at 2488 metres above sea level. You can get your strength back at the shelter where you will find a source of non-potable water. Continue to climb progressively and considerably to the 2860 metres of the pass in the vicinity of the Pessons peak and go along the ridge to the Collada de Pessons. This stretch of ridge offers views that will take your breath away after the height you have just climbed. Descend from the pass, at first with caution and then, progressively, the trail will become more and more gentle, until you are able to run at your leisure, but pay attention to the GPS because it is a popular area and there are a thousand paths that are not the right one, all bordering the lakes. Finally you will reach the Llac de Pessons restaurant, and from this point you will find the best part of the route in terms of running, travelling along wide ski slopes, and finally entering the shady forest of Canillo, which through very fun paths will take you to Canillo, the end of the stage.