Parque Nacional (PN) Puyehue is one of the greatest jewels in Chile's national park system. It is one of the most popular reserves, for both its easy accessibility and wide variety of activities. Created in 1941, PN Puyehue protects 107,000 hectares of Andean precordillera (foothills) and cordillera (range) landscape sculpted by glaciers, rivers and recent volcanic activity. Altitudes range from 250 meters (813 feet) in the Río Gol Gol valley to the 2236-meter (7267-foot) high Volcán Puyehue. Several legs of the Sendero de Chile cross the Andean plains and wrap around the base of the volcanoes. The Centro de Esquí on the skirt of Volcán Casablanca is considered the best in southern Chile and for days when you just want to relax, hot springs bubble and steam at the side of Río Chanleufú. In the Mapuche indigenous language, this little corner of paradise is the Place of Puyes, a freshwater fish: the Puyehue.

PN Puyehue's major volcanoes are Puyehue (2236 meters / 7267 feet), Casablanca (1990 meters / 6468 feet), Caldera del Fiucha (1481 meters / 4814 feet) and El Sarnoso (1630 meters / 5298 feet). El Cordón del Caulle (1793 meters / 5828 feet) is a fissure that radiates out from Volcán Puyehue. This is the park's most active volcanic feature and along its length are sulfur and hot springs, and geysers. Puyehue also has approximately twenty lakes and lagoons. Lago Constancia (1290 meters / 4193 feet altitude), Lago Gris (1080 meters / 3510 feet) and Lago El Paraíso (990 meters / 3218 feet) are the principal ones. Major rivers are the Pajaritos, the Gol-Gol (whose name in Mapudungún means big stick) and the Chanleufú (Braided River). These last two have typical, U-shaped glacier valleys.

More than 700 species of flora grow in these valleys and plains. The best time to catch flowers in bloom is from the end of November to mid-January. In general, PN Puyehue has humid evergreen forest with heavy undergrowth. Although primarily evergreen species, like the coigüe (Nothofagus dombeyi), the ulmo (Eucryphia cordifolia), the tepa (Laurelia philippiana), the tineo (Weinmannia trichosperma), the uma (Chilean myrtle, Amomyrtus luma) and the arrayán (Myrceugenella apiculata) grow here, some leaf-changing species, such as the lenga (enga beech, Nothofagus pumilio), the ñirre (Antarctic beech, Nothofagus Antarctica), the notro (Chilean fire bush, Embothrium coccineum) and the olivillo (Aextoxicon punctatum), are also present. PN Puyehue also contains some strains of alerce (Patagonian cypress, Fitzroya cupressoides), ciprés de las guaitecas (Guaitecas cypress, Pilgerodendron uviferum), and in the Antillanca sector, araucaria (monkey puzzle tree, Araucaria araucana). The many ferns also add a magical touch to the woodlands. The palmilla (Lophosoria quadripinnata) reaches almost three meters (10 feet) height and the transparent película (filmy fern, Hymenophyllum spp) is the smallest and most fragile. The abundant helecho costillo de vaca (Blechnum magellanicum) resembles, as its name implies, cow ribs. Multitudes of mosses carpet the earth, including the paragüita de sapo (Hydrocotyle spp) and the musgo pinito (Dendroligotrichum dendroides), one of the largest in South America, reaching a height of 70 centimeters (27.6 inches).

The fauna of PN Puyehue is equally as rich, and represents a large percentage of the species found in Chile. The area is home to thirty-eight varieties of mammals (27% of Chile's total) including the pudú (Chilean miniature deer, Pudu pudu), the guiña (kodkod, Oncifelis guigna), the comadrejita trompuda (Chilean shrew opossum, Rhyncholestes raphanunis), the monito del monte (austral opposum, Dromiciops gliroides), the coipo (nutria, Myocastor coypus), the huemul (South Andean deer, Hippocamelus bisulcus), the quique (lesser grison, Galictis cuja), the puma (Puma concolor) and the zorro gris (South American grey fox, Psuedolopex griseus). Eight introduced animals, like the visón (American mink, Mustela vison) and the jabalí (wild boar, Sus scrofa), are also present. Amphibians represent 35% of the variety found in the country, while reptiles and fish also find homes in this humid land. The majority of them are threatened species. Keep an eye out for the Ranita de Darwin (Darwin's frog, Rhinoderma darwinii), the culebra de cola corta (short tail snake, Tachymenis peruviana) and of course, the puye (whitebait, Galaxias macuiatus).

PN Puyehue is an ornithologist's Eden. The 126 types of birds represent 27.3% of Chile's known species. Twenty-two are endangered or threatened. Birdwatchers will have the best luck in spotting avian life during the migratory season, October through November. Some birds to train your binoculars on are the Condor (Vultur gryphus), the Aguilucho (White-throated Hawk, Buteo albigula), the Torcaza (Chilean Pigeon, Patagioenas (Columba) araucana), the Carpintero Negro (Magellanic Woodpecker, Campephilus magellanicus), the Caulle (Franklin’s gull, Larus pipixcan), the Huet-Huet (Black-throated Huet-Huet, Pteroptochos tarnii), the Huala (Great Grebe, Podiceps major), the Bandurria (Buff-necked Ibis, Theristicus caudatus), the Martín Pescador (Ringed Kingfisher, Ceryle torquata), the Zorzal (Austral Thrush, Turdua falklandii), the Chucao (Scelorchilus rubecula), the Queltehue (Southern Lapwing, Vanellus chilensis) and several varieties of ducks.

Overall, the climate in PN Puyehue is wet and cool. Precipitation in the park falls mostly in the months from May to August, but rain clothing is needed throughout the year. PN Puyehue has three general types of climate zones. The temperate rainy zone with Mediterranean influences receives from 180-400 millimeters (7-16 inches) of precipitation per year. The mountain climate, experienced at 400-1600 meters (1300-5200 feet), has snow from winter to spring. In summer (November-March) temperatures reach 14°C (57°F). In winter (June to October) they dip to 5°C (41°F), but you should prepare for below-freezing temperatures. The icy climate is found at higher altitudes, over 1600 meters (5200 feet). Within this zone is Volcán Casablanca, upon whose slopes you'll find the Centro de Esquí. It gets five to seven meters (192-276 inches) of precipitation annually and has a mean annual temperature of 3.5°C (38°F). In Sector Anticura, rainfall averages 2658 millimeters (105 inches) per year, with a mean temperature of 9.8°C (50°F). Aguas Calientes has 3633 millimeters (143 inches) of rain and mean temperatures of 8.8°C (48°F).

The park is divided into three sectors: Aguas Calientes, Antillanca and Anticura, and each has its own special attractions, trails and services. If you are doing the Sendero de Chile, you can camp wherever necessary along the route through the park. The nearest grocery stores are in Entre Lagos, where bencina (camp stove fuel) is also sold. There is cheaper lodging in Entre Lagos, 30 kilometers (18 miles) away. On the road between the Camino Internacional and Sector Aguas Calientes is Termas de Puyehue, an up-scale resort. No entry fee is charged for any of the sectors.

With each season come different opportunities for adventure. You can go hiking and trekking, or just soak in the hot springs, all year long, but other activities are only possible at certain times of year. From spring to fall you can undertake mountain climbing, bicycling, horseback riding and canopy tours. Sport fishing in the Gol-Gol, Chanleufú and Anticura rivers, and the Toro, Paraíso and Puyehue lakes is especially good during these months, however a license is required. During this warmer time of the year you can also climb the Puyehue and Casablanca Volcanoes, and Cerro Pantojo (previous authorization of and registration with Conaf is required). Spring and summer favor camping, picnicking, kayaking and hang gliding, and winter is the season for snow boarding and skiing at one of the most important ski centers in southern Chile. The season runs June 1-October 30 with Alpine skiing at Antillanca, and cross country skiing at Antillanca, Anticura and Volcán Puyehue.