Twenty-five kilometers south of Orotina, Highway 34 crosses the Río Tárcoles. The bridge over the river is the easiest place in the country for spotting crocodiles, which bask on the mud banks below the bridge: Don’t lean over too far. Several tourists have been victims of armed robberies here. There is now a police post, but caution is still required.

Crocodiles gather in even greater numbers at the rivermouth, near the fishing village of Tárcoles (the turnoff for Tárcoles is signed 5 km south of the bridge).

The estuary is also fantastic for bird-watching: More than 400 species have been identified here. Frigate birds wheel overhead, while cormorants and kingfishers fish in the lagoons. Roseate spoonbills add a splash of color. And scarlet macaws fly overhead on their way to and from roosts in the mangrove swamps that extend 15 kilometers northward.

At the turnoff for Tárcoles from Highway 34, a dirt road leads east and climbs steeply to the hamlet of Bijagual. About two kilometers above the road is the SkyWay, a canopy tour with bridges and fantastic views down over the coast. You must buy tickets ($20 adults, $10 children) at the Villa Lapas Hotel, which also operates a zipline Canopy Tour ($35 adult, $17 children). Continuing uphill, about five kilometers from Highway 34 you pass the trailhead to Catarata Manantial de Agua Viva (tel./fax 506/661-8263, 8 a.m.–3 p.m., $10 admission), a spectacular 183-meter-high waterfall. Best time is rainy season, when the falls are going full tilt. They don’t cascade in one great plume but rather tumble down the rock face to natural pools good for swimming. There are scarlet macaw nesting sites, and poison-arrow frogs hop along the paths. The trail is a stiff two-hour hike each way (take lots of water). A bus from Orotina to Bijagual will drop you at the front gate.

Another two kilometers brings you to Pura Vida Botanical Garden (tel. 506/200-5040, www.puravidagardensandwaterfalls.com, 7:30 a.m.–5 p.m., $15). Manicured gravel trails offer dramatic views over mountain ridges toward the Manantial de Agua Viva waterfall and the coast. A self-guided tour takes about one hour. It has a delightful restaurant and a gift store.