The araucaria forests of the Junín area are one of the most distinctive and otherworldly landscapes in South America. The trees — known in English as monkey puzzle trees — grow at elevations between 1,000 and 1,800 metres, their stiff, spiny branches radiating in perfect geometrical tiers from a straight trunk. Ancient specimens reach 40–50 metres in height with trunks over a metre in diameter. Walking among them feels like stepping into another era.
The best accessible araucaria forest is along the road from Junín to the Lanín park entrance, particularly on the slopes above Lago Huechulafquen. The trees are mixed with lenga beech at lower elevations; at higher altitudes the araucaria stands alone in open parkland with sweeping views.
Autumn (March–April) is spectacular in the mixed forests, when the lenga turns gold and copper against the dark green of the araucaria. In a good year the piñon (seed) crop in March and April attracts flocks of austral parakeets and various other birds to the treetops.