Rising above the fertile coastal plain of Quillota, Parque Nacional La Campana comprises 8,000 hectares of sheer-sided scrubland, scattered “oak” forests, and the greatest remaining concentration of the rare Chilean palm. A UNESCO World Biosphere Reserve since 1984, the former Jesuit hacienda of San Isidro is the place where temperate southern Chile’s forests reach their northernmost extent, overlapping the Norte Chico’s desert scrub.
Noteworthy for a network of integrated hiking trails that cross ridges and scale summits with spectacular views from the Pacific to the Andean summit of Aconcagua (across the border in Argentina), it is also a historic site. Trekking toward the Andes from Valparaíso  in the winter of 1834, Charles Darwin detoured to climb the summit of Cerro La Campana, an experience that he detailed in The Voyage of the Beagle.
Most of the sights are accessible by trails that crisscross the park or loop through it. Near the Granizo entrance, the Sendero La Canasta provides a good introduction to the forest, looping past several labeled trees and shrubs in the course of half an hour’s walk (the identifications on this nature trail, though, do not place the information in an ecological context).
More gratifying, if far more strenuous, is the seven-kilometer Sendero Andinista, from the Granizo entrance to the 1,880-meter summit of Cerro La Campana, where hikers can enjoy the same views that entranced Darwin. While the distance itself may not seem great and the climb is not technical, the 1,507-meter elevation gain means an average grade of almost 22 percent. For most people, it’s a full-day excursion, far more tiring than Patagonia’s famous Torres del Paine . Note that the hard-baked trail can be slippery even when dry, and wear suitable shoes.
Fortunately, most of the hike passes through shady forest and three cool springs with potable water: Primera Aguada, 580 meters above sea level, about an hour along the trail; Segunda Aguada, about the midway point, where camping is possible; and La Mina, the drive-in campground at the abandoned mine site (in dry weather, with a high-clearance vehicle, it’s possible to reach La Mina by road). Beyond the mine site, the trail becomes narrower and even steeper.
Sector Ocoa, at La Campana’s northern approach, is its largest sector, about 5,440 hectares. From Casino, two kilometers beyond the entrance station, the Sendero El Amasijo climbs gradually up the Estero Rabuco’s palm-filled gorge to the Portezuelo de Granizo saddle, where it bifurcates: the southern Sendero Los Robles descends to Sector Cajón Grande, while the Sendero Los Peumos heads west to Sector Granizo. Either route is a feasible day trip, but it’s also possible to camp in Estero Rabuco. Carry plenty of water since, except for a spring just below the Portezuelo de Granizo, livestock have made the streams unpotable.
Also at Sector Ocoa, the Sendero La Cascada is a four-hour round-trip to an attractive waterfall; there are several other shorter trails in the area.
Within the park, camping is the only option. Organized camping for up to six people costs US$11 at Conaf’s Sector Granizo (23 sites), Sector Cajón Grande (22 sites), and Sector Ocoa (16 sites). Backcountry camping is possible, but only with Conaf permission in an area that is steep, rocky, and fire-prone.
Half a block off Olmué’s Plaza de Armas, Hostería Copihue (Diego Portales 2203, tel. 033/441544, www.copihue.cl , US$65/95–78/112 s/d with breakfast), a 40-suite resort with pool, tennis courts, and other luxuries, gives major discounts out of season. Half-board and full-board packages are also available.
Also in Olmué, Parador de Betty (Av. Eastman 4801, tel. 033/441511) does Chilean country cooking—pastel de choclo, humitas, cazuelas and the like—at a very high level. The last weekend in March, it hosts the annual Festival de la Comida del Huaso to showcase the best of rural food and other products, to the accompaniment of folkloric music and dance.
At each park entrance, Conaf rangers collect a US$2.80 admission fee (seniors and children pay half).
The Granizo ranger station occasionally has maps, for a small charge, and usually has books on flora, fauna, and other conservation topics. Visitors specifically interested in flora can buy Rodrigo Villaseñor Castro’s inexpensive (Spanish-only) Guía para el Reconocimiento de las Especies Arbóreas y Arbustivas en el Parque Nacional La Campana (1998), a joint publication of Conaf and Valparaíso ’s Universidad de Playa Ancha.
La Campana is readily accessible from Valparaíso  and Viña del Mar , less so from Santiago . From Valparaíso’s Estación Puerto, Merval trains take an hour to reach Limache, where taxi colectivos shuttle back and forth to Olmué and the Granizo entrance.
From Santiago, any northbound bus along the Panamericana can drop passengers at Hijuelas, where an ill-marked gravel road heads south just before the main highway bridge over the Río Aconcagua. There is no regular public transportation on this gravel road, which is 12 kilometers from the Ocoa entrance.