sentences:  Among the attractions in the park are the Llaima volcano, Sierra Nevada and wild landscapes characterized by islands of vegetation completely surrounded by vast areas of lava flows.Extensive forests, formed mainly by Araucarias and "Nothofagus" species, and small lakes increase the scenic beauty of the park.It is also known as "Los Paraguas" (The Umbrellas), due to the shape of the Monkey Puzzle trees.