Built in 1976, Explorer’s Inn (Lima tel. 01/447-8888, www.explorersinn.com, three days/two nights US$198 pp in double room; US$238 pp in single room) is the oldest, most experienced ecolodge in Puerto Maldonado and has a comfortable, worn-in feel.

The palm-thatched, wood-rich bungalows have foam mattresses, palm-wood walls, en suite bathrooms (but no hot water), and are romantically lit by candles at night. They are comfortable but not luxurious. The central dining room is made entirely of wood and has an upstairs library with a number of natural history exhibits left behind by biologists and other researchers who have worked here over the decades.

Compared to other Amazon lodges, Explorer’s Inn has the best combination of convenience, prices, and biodiverse rainforest. It is one of few located within Tambopata National Reserve, and it carefully manages 5,500 hectares of pristine rainforest that began as a private reserve and has since been incorporated into the new Tambopata National Reserve (the private property of the lodge is 105 hectares). The owner, Max Gunther, speaks flawless English, as well as German, and has been a leading figure in Peruvian ecotourism and conservation for three decades.

Biologists have proclaimed the 5,500 hectares surrounding the lodge to be “the most biodiverse place on the planet” because of a number of Guinness World Records that have been set there for animal species, including 600 bird species and more than 1,235 types of butterfly. Beside the lodge is located the new Max Gunther Centre, a made to order research station built by Lima’s Catolica University, which is used by many visiting biologists from around the world. The lodge also runs a volunteer resident naturalist program designed to appeal to graduates of the environmental sciences eager to gain experience in the Amazon rainforest.

There are 37 kilometers of well-marked trails that lead to huge tracts of virgin forest, a small macaw clay lick, and two lakes where giant otters live. In one two-hour walk, we saw 20 bird species, including macaws and toucans, howler monkeys, otters, and a meter-long coral snake. The guides are extremely knowledgeable, and most tours include a visit to a farm in the nearby community of La Torre.

The lodge also arranges other trips, including a mystic adventure with an ayahuasca session, a trip to the macaw clay lick on the Río Tambopata, a six-night bird-watchers program, and a variety of camping trips with the chance of observing tapirs at a salt lick at night. The lodge is 1.5 hours upstream from the native community of Infierno.