The Amazon basin is home to the world's vastest rainforest as well as the planet's largest river by volume. Over 13% of this immense jungle (and an ever larger percentage of its unspoiled area) lies within the borders of Peru, where it occupies over half of the country's territory yet accounts for only about 11% of its population. The Peruvian Amazon comprises two distinct ecoregions, the largest of these being the lowland jungle region at 262 to 1,312 feet (80 to 400 meter) above sea level, where the average temperature is 82°F (28 °C), there is high relative humidity and rainfall is abundant. Along the eastern edge of the Andes, between 1,312 and 3,280 feet (400 to 1000 meters) above sea level, lies the highland jungle region, where temperatures vary depending on altitude and the rugged terrain has given rise to many endemic species. The Peruvian Amazon as a whole is one of the most biodiverse places on earth, with over 50,000 plant, 1,700 bird, 400 mammal and 300 reptile species, and scientists continue to discover new species all the time. A number of national parks and reserves now protect vast tracts of this tropical wilderness where large numbers of indigenous people still live and which has grown into a popular tourist destination. Here visitors can trek in the jungle, see exotic animals in the wild, experience river life, visit native villages, stay overnight at a jungle lodge and otherwise fully immerse themselves in this utterly enchanting place, one of the world's last true frontiers.

Peru's jungle region can be divided into three sections—north, central and south—with the northern and southern regions holding the greatest allure. The city of Iquitos is a gateway to the northern jungle, where the Pacaya-Samiria National Reserve is the largest protected area, and the southern jungle's main attractions are the Manu Biosphere Reserve, the Tambopata-Candamo Reserve and the Bahuaja-Sonene National Park. The province of Chanchamayo and the city of Pucallpa are the most important tourist areas of the central jungle.

A green world Capital of the remote Loreto region, Iquitos is the country's largest Amazonian port city and quite possibly the largest city in the world that can't be reached by road. A vibrant city with exceptionally friendly and fun-loving people and hot nightlife, it has some of the Peruvian Amazon's best tourist facilities and services. Travelers fly in from Lima and use the city as a starting point for Amazon River cruises and rainforest excursions to the Pacaya-Samiria National Reserve, for example. Hard-to-reach and brimful with some of the Amazon's most amazing wildlife, this gorgeous unspoiled reserve is Peru's second-largest protected area and home to some 30,000 indigenous people.

In Peru's southern jungle region, the Manu Biosphere Reserve stands out as the country's largest protected area and the most species-rich park on the planet. Remote and exceptionally pristine, it spans cloud forest terrain in the foothills of the Andes down to dense lowland rainforest and a few native tribes still roam its lands. One of the best places in the world for birding, Manu is a great place for viewing wildlife in general given that the absence of hunting has made animals less wary of humans. Further south near the Bolivian border, the contiguous Tambopata-Candamo Reserve and Bahuaja-Sonene National Park encompass an immense area of virgin rainforest that ranks among the world's finest and most biodiverse, thanks to its varied elevation and dozen different kinds of forest. It's home to the largest macaw clay-lick on earth and you'll find more species of birds and butterflies here than any other place of the same size in the world. More easily accessible than Manu, which entails a lengthy trip from Cuzco, a brief flight to Puerto Maldonado followed by a few hours' boat ride will take you to Tambopata.

The toco toucan in flight Peru's central rainforest destinations offer the advantage of easier overland access. Chanchamayo's cloud forests nestled in the Andean foothills are an eight-to-twelve hours' bus ride from Lima, and while the lively port of Pucallpa is best reached via plane there is a decent road linking it to Tingo María and beyond. Pucallpa has some nearby indigenous communities and jungle lodges, and riverboats destined for Iquitos depart from here.

The Peruvian Amazon receives the most rain November to April, is drier May to October and is hottest February through June. Visiting during the rainy season may be ideal for wildlife viewing, as well as for Amazon cruises, but mosquitoes are the worst at this time and roads may be impassable. So plan accordingly, get the necessary vaccinations and brace yourself for a truly eye-popping adventure.