Chirripó National Park($15 admission two days, $15 each extra day) protects 50,150 hectares of high-elevation terrain surrounding Cerro Chirripó (3,819 m), Costa Rica’s highest peak. The park is contiguous with La Amistad International Park  to the south; together they form the Amistad-Talamanca Regional Conservation Unit. Flora and fauna thrive here relatively unmolested by humans.
One remote section of the park is called Savannah of the Lions, after its large population of pumas. Tapirs and jaguars are common, though rarely seen; the forests also protect several hundred bird species. Cloud forest, above 2,500 meters, covers almost half the park, which features three distinct life zones. The park is topped off by subalpine rainy páramo, marked by contorted dwarf trees and marshy grasses.
Cerro Chirripó was held sacred by pre-Columbian peoples. Tribal leaders and shamans performed rituals atop the lofty shrine; lesser mortals who ventured up Chirripó were killed.
Just as Sir Edmund Hillary climbed Everest “because it was there,” so Chirripó lures the intrepid who seek the satisfaction of climbing to the Chirripó summit . Many Ticos choose to hike the mountain during the week preceding Easter, when the weather is usually dry. Avoid holidays, when the huts may be full. The hike from San Gerardo ascends 2,500 meters and is no Sunday picnic but requires no technical expertise. The trails are well marked but steep and slippery.
The park service is pushing the lesser-known Herradura trail (minimum three days/two nights), via Paso de los Indios, with the first night atop Cerro Urán.
The weather is unpredictable—dress accordingly. When the bitterly cold wind kicks in, the humidity and wind-chill factor can drop temperatures to freezing. Rain is always a possibility, even in “dry season,” and a short downpour usually occurs mid-afternoon. Fog is almost a daily occurrence at higher elevations, often forming in midmorning. Temperatures can fall below freezing at night. February and March are the driest months.
The mountain plays host to the annual Carrera Internacional Campo Traviesa de Chirripó (www.carrerachirripo.com ) each February, a rugged race to the top and back!
No guides are required for hiking the Termómetro trail, but they are compulsory for the Herradura trail. The communities of San Gerardo and Herradura run an association of guides and porters (arrieros, tel. 506/2742-5225). Prices are fixed at $60 per day, with a 35-pound limit per porter. If you want to attempt the Herradura trail, check with the pulpería (tel. 506/742-5066) in Herradura.
You can rent tents, stoves, sleeping bags, and other equipment at Roca Dura and Cabinas del Descanso; stoves are permitted only within the Los Crestones hut. Be sure to bring the following:
There’s a cave refuge halfway up the mountain, and an open-air hut, Refugio Llano Bonito, with a one-night limit ($5). The main lodge—Centro Ambientalista El Páramo (tel. 506/2206-5080, $10 pp per night), “Los Crestones”—is 14 kilometers from the trailhead and has four bunks (with foam pads) to each of 15 rooms, and shared bathrooms with lukewarm showers, a communal kitchen, and solar-powered electricity 6–8 P.M. You can reserve meals; otherwise, you need to cook for yourself.
Camping is not permitted except at Camping Chirripó, 10 kilometers from the trailhead on the Herradura trail (eight people maximum; reservations are required).
The ranger station (tel. 506/2742-5083 or 2200-5348, 6:30 A.M.–4:30 P.M. daily) in San Gerardo de Rivas has toilets. If you plan on going solo, consider buying the 1:50,000 topographical survey (sections 3444 II San Isidro and 3544 III Durika) in advance; if you plan on hiking to nearby peaks, you may also need sections 3544 IV Fila Norte and 3444 I Cuerici, available from the Instituto Geográfico Nacional in San José.
Only 40 visitors are allowed within the park at any one time. Only 10 spaces daily are available for people arriving without reservations; the other 30 spaces are for people with reservations. Reservations (tel. 506/2742-5083) are accepted Monday–Friday only, to be prepaid via the Banco Nacional. Experienced hikers recommend showing up anyway, as there are usually some no-shows.
Costa Rica Trekking Adventure (tel. 506/2771-4582, www.chirripo.com ), in San Isidro, offers guided treks.