The GRP can be found here, signed in red and yellow, at Basses de Port de Rat, from where you climb to the Port de Rat, which marks the French border. A technical descent to a small lake is not a chance to recover, and once you reach the lake turn to the left to face the demanding climb up Coll d’Arsinal, climbing to 2700 metres above sea level.  At the summit, the Estanys de Montmantell are laid out before you, and you pass them on the right to continue to descend to the headwaters of the Pla d’Estany, riding alongside the river, where before reaching the refuge you will once again meet the markers for the GRP. Follow the GRP to the right, on ground that is broken in sections, to reach Estanys Forcats, impressive mountain lakes which are frozen 10 months of the year. Above the lakes, you will find the Lodge of Estanys Forcats, a wooden structure protected by stones, where you can shelter if the weather suddenly changes.

From the Lodge, continue to climb the Collada dels Estanys Forcats, from which you descend rapidly, through boulders or snow depending on the season, to the Estanys de Baiau, now in Catalonia. From the lakes, climb through scree and broken ground to Portella de Baiau, back into Andorra, to climb up to the summit of Baiau and follow the ridge to the highest point in the country, Comapedrosa at 2941 metres. From the summit, descend following the ridge line over broken ground. At Estany Negre rejoin the GRP to descend fast to the Refuge at Comapedrosa, the country's first refuge with a warden. At the refuge, turn right to approach the last climb of the route, the Collada de Sanfons, which is not a difficult climb, and finish off the circuit climbing Pic del Port Vell and then descend to Port Vell.

From there you can see the ski lifts at Arinsal, go towards them and then make a fast descent down the ski slopes back to your starting point. 

WATER: Arinsal/you will find no end of lakes and rivers during the route where you can refill with water. We recommend taking mineral salts or water-purifying tablets.