Lago Todos los Santos, in the heart of Vicente Pérez Rosales National Park, is one of the most striking lakes in South America. Its colour — a deep, glowing emerald-green — comes from glacial sediment suspended in the water. The lake is twenty kilometres long, almost completely undeveloped, and ringed by the cones of Osorno, Puntiagudo, and Tronador.
The little village of Petrohué at the western end has a hotel, a CONAF office, and the dock for the small ferry that crosses to Peulla in the east. Day tourists from Puerto Varas usually just take a short scenic cruise from the dock. Those crossing to Argentina via the Cruce Andino take the longer ferry to Peulla and then continue by bus and another boat to Bariloche.