Through the Río Lácteo Valley you access the base of Cerro San Lorenzo and its vertical face of 2000 m. Below the peak, Laguna de los Témpanos often contains huge blocks of ice from the Lácteo Glacier. Along the trail you see a landscape recently molded by the retreat of glaciers and other geoforms including a massive alluvial fan.
The parking lot / trailhead is 20 km from the Onelli Information Center. It is necessary to cross a stream at the beginning of the trail, about 250 meters later is the first hut Refugio Gilberto (capacity for 4-6 people). 11.5 km north is Refugio Kris y Doug Tompkins (capacity for 3 people), three domes nearby the hut with capacity for 1 to 4 people each, and the San Lorenzo backcountry campsite with 12 tent sites. The trail to Laguna de los Témpanos of 5.2 km (one way) starts near Refugio Kris y Doug Tompkins, at the beginning there is a ford to cross the Hermoso River. It is recommended to take extra footwear for the Hermoso River crossing.
We suggest the Río Lácteo Valley Trail when there is a lot of wind, given that a good part of it is protected from the predominant winds.