A large, forested region, with a manic climate (usually searingly hot and humid, but with sudden cold spells – friajes – between June and August, due to icy winds coming down from the Andean glaciers), the southern selva has only been systematically explored since the 1950s.
Named after the broad river that flows through the heart of the southern jungle, the still relatively wild departamento of MADRE DE DIOS is centred on the fast-growing river town of Puerto Maldonado, near the Bolivian border and just 180m above sea level. The town extends a tenuous political and economic hold over the vast departamento and has a fast-growing population of over 40,000, but most visitors come for the nearby wildlife, either in the strictly protected Manu Biosphere Reserve – still essentially an expedition zone – and the cheaper and easy-to-access Reserva Nacional Tambopata, chiefly visited by groups staying at lodges. Both offer some of the most luxuriant jungle and richest flora and fauna in the world. Another massive protected area, the Parque Nacional Bahuaja-Sonene, is adjacent to Tambopata.
Less accessible than the protected zones, but nevertheless offering travellers staying in Puerto Maldonado a taste of the rainforest, are Lago Sandoval and the huge expanse of Lago Valencia, both great wildlife spots east along the Río Madre de Dios and close to the Bolivian border. At the least, you’re likely to spot a few caimans and the strange hoatzin bird, and if you’re very lucky, larger mammals such as capybara, tapir or, less likely, jaguar – and at Valencia, you can fish for piranha. A little further southeast lies the Pampas del Heath, the only tropical grassland within Peru.
The Río Madre de Dios itself is fed by two main tributaries, the Río Manu and the Río Alto Madre de Dios, which roll off the Paucartambo Ridge just north of Cusco. West of this ridge, the Río Urubamba watershed starts and its river flows on past Machu Picchu and down to the jungle area around the town of Quillabamba, before entering lowland Amazon beyond the rapids of Pongo de Mainique.