From the Gendarmeria (border guards) Tromen, take the path going north toward the mountain behind the gendarmerie (Camino de Mulas). Go during 1h approximately until the "forest of Lenga", or toward a very well defined lateral moraine. Climb the moraine and keep going up on its ridge, until reaching the slopes of the Lanin. This is called the "the Espina del Pescado" (fish bone). Follow paths toward the west (right), heading up all the time as well. You will reach, afterv some 3 hrs, the first shelter called "refugio RIM". (Regimiento de Infateria de Montaña, 20 people, 2450mts). You can either stay here or keep going to the second shelter, "refugio CAJA", 1 hour or less higher (Club Andino Junin de los Andes, 14 people, 2600 ) There is another shelter little lower east, along an alternate path called "Sendero of mulas".
After one night with the refuge, the route is direct on the left towards the top by leaving the glacier (there is no more path). It is better with snow (before March, there is sufficiently in theory), because the stones is rather large and blocks walk. Attention not to be lost with the descent in the event of fog, it is not always easy to find the refuge.
Follow paths toward the west (right), heading up all the time as well. You will reach, after some 3 hrs, the first shelter called "refugio RIM". (10 people). Yiou can either stay here or keep going to the second shelter, "refugio CAJA"(6 people) 1 hour or less higher. There is another shelter little lower east, along an alternate path called "Sendero of mulas".
You can start early the next morning and, going towards the left and toward the top. You can zigzag, go direct or what ever you want to do. Just be sure you enter the top carefully since winds are bery strong sometimes, and try not to fall on the south side of the mountain which has a fantastic, steep ice-snow wall (it has been climbed I heard)
Desent: the same.
Basic glacier travel. Can be done without ice axe but why do you want to do that? Take it. Rope and wind protection.
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