“Forward, back, get down,” shouts Antonio, our river-rafting guide.

The bright-blue rubber raft swirls, twists, turns. Rocks loom, the raft heaves, as we navigate the raging rapids in Costa Rica ’s fast-flowing Pacuare River. “They’re only class II,” he yells, “wait until you get to class IV.”

We bump and wind through rock canyon walls deep in the rain forest, over rapids sideways, backwards, past a cascading waterfall. The river widens and the turbulence ceases. After just over an hour on the water, we sight the Pacuare Lodge’s thatched-roof bungalows. Our gear, safely stowed in red rubber bags, is unloaded. The manager, Willman Salanos, greets us with, “There is no electricity. Be sure and carry your flashlight to happy hour. It gets dark at six o’clock.”

Soaring over the forest on a zip line is among the lodge activities.

This environmentally sensitive lodge with its nine bungalows set in an untouched tropical wilderness is the only lodge in the country where practically everything, including most guests, arrive by raft.

I reach my cabin by a stone path that winds its way through a swath of lush green grass. It’s set in a gardenlike setting of tropical plants and giant ceiba, or floss silk trees.

The screened bungalow with its polished teak floors, queen-size bed and down-filled pillows, plus a candle and a wind-up flashlight on the bedside table, offers a unique form of luxury. The open-air bathroom with a privacy screen of dark-green foliage uses solar-heated hot water flowing into a burnished copper sink. A lush arrangement of brilliant red tropical flowers rests beside a wooden stand holding oversize white towels.

The owners of this luxury jungle oasis are serious about preserving the fragile ecology. Instead of cutting down endangered rain forest to build the bungalows, they brought in wood from a sustainable tree plantation by raft. Local Cabecar Indians thatched the palm-leafed, conical roofs in their traditional way. With no electricity, the candles, flashlights and lanterns offer conservation with a romantic ambiance.

At happy hour, guests gather at the rustic bamboo bar upstairs in the two-story main building to nibble on yucca chips and trade stories about the joys and pitfalls of traveling. This is only prep time for a candlelit gourmet dinner served communal style on a long table in the lodge’s downstairs dining area.

An evening meal might include a fish filet baked in plantain leaves accented with a touch of herbs, white wine and fresh cream, served with a local specialty of cassava, fried breadfruit or wild rice, and organic vegetables. For a grand finale, an organic chocolate torte is served with rum-vanilla ice cream topped with crystallized ginger. The river guides–turned–waiters, wearing large white aprons, keep the wine flowing.

Trips usually last two or three days and include soaring over the top of the rain forest while safely anchored to a steel cable — a once-in-a-lifetime event.