In autumn we slept in a tent inside the "refugio amarillo" and we were happy to have our tent as the wind pressed the snow inside the shelter. It´s the highest shelter of Lanín. It is compulsatory to make a reservation online at Lanín National Park if you want to sleep here: Rservation at: qsistemas.com.ar/lanin/login.php (you will have to generate a Login) and follow the instructions (in Spanish!).