Southwest of Buenos Aires, at Paso Real (there is no community as such), the Río El General and Río Coto Brus merge to form the Río Grande de Terraba, which swings west and runs through a ravine in the Fila Costeña mountains, connecting the Valle de El General to Palmar and the Golfo Dulce region; the Pan-American Highway follows the river.

South of the junction of the two rivers, the Valle de Coto Brus is drained by the Río Coto Brus and its tributaries. This was once a center for coffee production, but the industry has declined in recent years. The summits of Cerro Kamuk (3,549 m) and Cerro Fabrega (3,336 m) loom massively overhead. The Río Térraba is spanned by a bridge one kilometer south of Paso Real. From here, Highway 237 leads to San Vito, the regional capital, on a ridge at the head of the valley. It’s one of the most scenic drives in the country.

Boruca

About 10 kilometers south of Paso Real, a dirt road leads sharply uphill and runs along a ridge (offering fantastic views) to Reserva Indígena Boruca, in the Fila Sinancra, comprising a series of Indian villages scattered throughout the mountains. The main village is Boruca, a slow-paced hamlet set in a verdant valley in the heart of the reserve.

There’s a tiny Museo Comunitario Boruca (tel. 506/2514-0045 or 2730-1673, www.borucacr.org, 9 A.M.–4 P.M. daily, free) honoring the local culture; signs are in English, German, and Spanish. It’s funded by the sale of beautiful carved balsa-wood masks, natural cotton weavings made on back-strap looms, and other traditional crafts made by artisans of the Flor Co-operativa (Sô Cagrú, “masked warrior” in the local language), headed by Marina Lázaro Morales.

Community tours offer an opportunity to learn about traditional weaving and the creation of “warrior” masks meant to scare away evil spirits.

Try to visit for the Festival de los Diablitos (Dec. 30–Jan. 2). Every year on December 30, a conch shell sounds at midnight across the dark hills of the Fila Sinancra. Men disguised as devils burst from the hills into Boruca and go from house to house, performing skits and receiving rewards of tamales and chicha, the traditional corn liquor. Drums and flutes play while villagers dressed in burlap sacks and traditional balsa-wood masks perform the Fiesta de los Diablitos. Another dresses as a bull. Plied with chicha, the diablitos chase, prod, and taunt the bull. Three days of celebrations and performances end with the symbolic killing of the bull, which is then reduced to ashes on a pyre. The festival reenacts the battles between native forebears and Spanish conquistadors with a dramatic twist: The native people win.

The Bar, Soda y Cabinas Boruca (no tel., $10 pp) has five basic rooms with private cold-water baths. You can also stay with local families by prior arrangement. Lourdes Frasser (tel. 506/2730-2453, artelocagru [at] yahoo [dot] es) has a thatched guest rancho with bamboo-enclosed outside toilet and shower.

Buses depart Buenos Aires for Boruca at 11 A.M. and 3:30 P.M. daily (90 minutes). The return bus departs Boruca at 6:30 A.M. and 1 P.M.