The southeast shores of Osa are lined with hidden beaches—Playa Tamales, Playa Sombrero—in the lee of craggy headlands, notably Cabo Matapalo at the southeast tip of the Osa Peninsula about 18 kilometers south of Puerto Jiménez.

This section of coast is popular with surfers, who come for the powerful six-foot waves, especially in summer. At Matapalo, a side road leads through an arched “gate” and winds three kilometers to the beach at Cabo Matapalo.

The rough dirt road peters out at Carate, 43 kilometers from Puerto Jiménez, consisting of an airstrip and a small pulpería (grocery). About three kilometers east of Carate, you pass Laguna Pejeperrito, good for spotting crocodiles, caimans, and waterfowl.

The road to Carate takes about two hours under good conditions. It gets gradually narrower and bumpier and muddier.

Note: There are several rivers to ford, and they may be impassable in wet season. A high-clearance, 4WD vehicle is essential, but no guarantee of passage. The Río Agua Buena is the real challenge, but even the narrow and seemingly innocuous Río Carbonera, which pours into the sea near Matapalo, has washed vehicles downriver after torrential rains.

You can charter an airplane to Carate, but the airstrip sometimes floods in wet season. A colectivo truck (tel. 506/2837-3120, $8 pp one-way, two hours) runs daily from Puerto Jiménez at 6 A.M. and 1:30 P.M. daily, departing Carate for Puerto Jiménez at 8:30 A.M. and 4 P.M. ($7). It stops at Matapalo ($4). You can also rent a Jeep-taxi ($80–100 per carload).

Cabo Matapalo

Encanta la Vida (tel. 506/2735-5678, www.encantalavida.com, $100 pp including meals), in the gated community of Matapalo, is a three-story wooden lodge, handsomely decorated and fringed by wide verandas with hammocks and rockers with views over both ocean and jungle. It has two beautiful suites plus a honeymoon suite, all with mosquito nets over four-poster rough-hewn beds and huge walk-in showers. It requires a two-day minimum stay.

The Spanish- and German-run El Remanso Lodge (tel./fax 506/2735-5569, www.elremanso.com, $135–210 s, $270–340 d low season; $145–235 s, $290–390 d high season, including meals), atop Cabo Matapalo, is an eco-friendly entity running entirely on its own hydroelectric power. It offers seven spacious and airy cabins, with sponge-washed concrete floors and a gorgeous, simple aesthetic that includes soft-contoured concrete bed bases, batik covers, hammocks, and wall-to-wall louvered windows to three sides. It also has a two-story group cabin for four people, plus a six-bedroom house with king-size beds, glazed concrete floors, and handsome dark-stone tubs. It has a beautiful restaurant, a deck with plunge pool, and a zip line. An open-air restaurant has stylish rattan lounge chairs.

A deluxe gem, Bosque del Cabo (tel./fax 506/2735-5206, www.bosquedelcabo.com, $145–250 s, $230–330 d low season; $200–285 s, $330–440 d high season) nestles atop the 180-meter cliff of Cabo Matapalo and part of a 250-hectare forest reserve. It upgraded with a stylish palenque restaurant and lounge-bar with poured-concrete sofas with Guatemalan cushions. Set in landscaped grounds are seven thatched cliff-top cabinas with superb ocean views. Screened open-air showers have their own little gardens; verandas have hammocks. Three splendid deluxe cabins each have terra-cotta floors, king-size bed with mosquito net, chic decor, and lofty rough-hewn stable doors that open to a wraparound veranda with sublime ocean vistas. Then there’s the Casa Blanca and Casa Miramar, exquisitely decorated two-bedroom villas. Budget travelers get two much simpler cabins, accessed by a muddy forest trail and suspension bridge. Lanterns light the place at night. There’s a cooling-off pool fed by spring waters, a sundeck, and a yoga platform. It offers hikes and horseback rides, and there’s a zip-line canopy tour.

The world-renowned Lapa Ríos (tel. 506/2735-5281, www.laparios.com, $370 s or $480 d low season, $540 s or $760 d high season, including meals) is an exquisite eco-conscious resort with a great location atop a ridge overlooking Cabo Matapalo. Sixteen romantic, luxuriously appointed bungalows reached by wooden walkways feature gleaming hardwood floors, screened windows, gorgeous stone-lined bathrooms, patio garden complete with outdoor shower, and louvered french doors opening to private terraces. The thatched lodge has a spiral staircase augering up from the restaurant to a mirador (lookout platform). There’s a small pool with sundeck and bar. The property is backed by a 400-hectare private reserve. Walks in the rainforest, kayaking, horseback rides, and a full-day Corcovado tour with air transfers to/from Sirena are offered. Despite being ridiculously overpriced, this place is marvelous, and it fills up. It’s one of only 11 hotels in the country with five leaves in the Certification for Sustainable Tourism program.

Lapa Ríos offers superb gourmet dishes in its Restaurante Brisas Azul (www.laparios.com, 7 A.M.–8:30 A.M. daily, $5–25). It’s worth the drive just for the carrot cake! Come on Wednesday or Saturday for the tortilla-making class.

Near Matapalo, the eclectic Buena Esperanza (tel. 506/2735-5531, martinatica [at] hotmail [dot] com, $25 pp), aka Martina’s, is beloved by surfers and backpackers for its colorful Moroccan-style decor and unique arrangement—its windowless, open-sided cabinas have low cement walls with wrap-around sofas with batiks and Army-fatigue cushions, sponge-washed concrete floors, and rough-hewn beds with mosquito nets. Shared outdoor showers and toilets have cold water only. Its offbeat bar-restaurant is a popular hangout. Rates include breakfast.

I like the offbeat German-run Ojo del Mar B&B (tel. 506/2735-5531, www.ojodelmar.com, $45 s or $60 d tents, from $75 s or $100 d cabin), enjoying a secluded forest setting near Matapalo. It has two open-sided bamboo cabins with private rainforest showers, plus two double beds with batiks and mosquito nets (one cabin has a loft bedroom). Two simple bamboo tiki tents have private outdoor showers but share a communal bathroom. Meals are served in a charming Robinson Crusoe–style dining area. It has no electricity. Rates include breakfast.

The Buena Esperanza (tel. 506/2735-5531, 9 A.M.–midnight daily) draws surfers for its tremendous offbeat ambience and international cuisine (such as Thai and Mexican) at budget prices. It’s the only bar hereabouts and gets lively with a mix of foreigners and locals.

Carate

You can camp at Carate in front of the pulpería, which has bathrooms, showers, and a water faucet. It also has five basic cabinas without fans, and with cold water only ($10 pp).

Seeking a safari-style experience? La Leona Ecolodge (tel. 506/2735-5704, www.laleonaecolodge.com, from $79 s or $95 d), just 200 meters from the La Leona ranger station, is a simple tent camp with 17 tent-cabins on wooden platforms, each with two small mattress-beds. They share a bathhouse with four bathrooms and showers.

Meanwhile, also at Carate, Finca Exótica (tel. 506/2735-5230, www.fincaexotica.com, $70 s/d tent, $120 s or $200 d cabin low season; $80 s/d tent, $135 s or $220 d cabin high season, including all meals) offers lovely A-frame safari-style open-air thatched cabins plus safari-style tents (most with private outdoor shower). Plus there’s a fully equipped two-story cabin for rent. The owners pay special attention to serving healthy gourmet meals. Tours here include hikes in the private rainforest refuge. The lodge itself is a delightful place to relax, and a yoga platform is being added. You get real value for money here.

The Lookout Inn (tel./fax 506/2735-5431, www.lookout-inn.com, $95–175 pp including meals) sits on the hillside one kilometer east of Carate. Terry and Wendy, from New Mexico, are live-in owners of this three-story house with seven tall-ceilinged, tastefully decorated bedrooms. Sponge-washed walls merge with bamboo furnishings and tropical hardwood accents, not least bed frames made from tree trunks. The owners have been expanding up a storm, adding open-air A-frame tiki-huts, an open-air tree-house cabin, a beach bungalow, and several other options. A lounge has a small library. A spiral staircase opens onto a mirador with hammocks, a telescope, and fabulous vistas. A swimming pool and deck are inset in the garden below, and a pond draws poison-dart frogs. Guests get free use of kayaks, canoes, mountain bikes, and boogie boards.

A winner is the calming Luna Lodge (tel. 506/8380-5036, U.S. tel. 888/409-8448, www.lunalodge.com, $105–195 s or $200–290 d low season; $120–240 s or $210–350 d high season including taxes, meals, and tour), nestling in the hills above Carate amid primary rainforest and centered on a massive thatched rancho reception lounge-restaurant with deck offering fabulous views. Eight circular bungalows are simply yet delightfully furnished; they stair-step the hill, reached via paths of black slate. Exquisite rainforest bathrooms have shower-tubs enclosed by a stone wall with garden. There are also five safari-style budget tents reached by a stiff uphill climb. The bar and restaurant serves international cuisine. A wellness center offers yoga, tai chi, and massage, plus there’s a lovely solar-heated pool. To get there, you have to crisscross the Río Carate several times; the river is often impassable! Fortunately, once across, the steep hill is paved.

The Corcovado Lodge (c/o Costa Rica Expeditions, tel. 506/2257-0766, www.costaricaexpeditions.com), 1.5 kilometers west of Carate, will reopen in 2012 as an all-inclusive, with 10 deluxe tree-house cabins, each with a king-size bed, wall-to-ceiling screens, and decks with lounge chairs and plunge pool.