After breakfast, fly to Iquitos in the Peruvian Amazon and continue overland to the riverside village of Nauta, where the Delfin II awaits. Settle into your cabin and gather for a welcome dinner of fine Peruvian cuisine on board. Tonight, step out on deck to gaze at the magnificent Amazon night sky.

Spend this week exploring the Pacaya-Samiria National Reserve, a pristine swath of jungle stretching more than five million acres and harboring some of the Amazon’s most diverse flora and fauna. The reserve is bordered by the Marañón and the Ucayali, two powerful rivers that converge to create the famed Amazon, which floods annually with nutrient-rich waters and is known locally as the Mirrored Forest for the reflections created by its glassy water.

Set out into this remarkable wilderness on daily excursions by skiff, kayak, and, when the water level permits, hikes on dry land. Skim past giant lily pads afloat on blackwater lakes, and venture deep into the rainforest on narrow tributaries. Look for sloths and monkeys, including variably colored saddleback tamarins, noisy howlers, and shaggy-tailed saki monkeys. Watch for an astounding variety of birds, from tanagers and hummingbirds to parrots and endangered scarlet macaws. In the river, look for massive paiche fish, the Amazon’s largest; rare pink dolphins; and the infamous piranhas.

Enjoy an opportunity to swim in a lake in the reserve’s interior. Seek out Victoria amazonica, a giant water lily that grows in small lagoons. Go on a bird-watching hike, listening for the vocal oropendola and then looking for its telltale yellow tail. Watch the sun set and listen to a cacophonous symphony of nocturnal animals calling out across the treetops. Then slip through the forest in a skiff as night falls, using a spotlight to find caimans, frogs, fishing bats, and other creatures of the night.

One of the unexpected joys of traveling in the Upper Amazon of Peru is interacting with the local ribereños, the traditional people who live on the riverbanks. Visit one of the local communities and see the projects that National Geographic-Lindblad Expeditions supports through a local nonprofit, including a variety of handicrafts, women’s health initiatives, and sustainable farming.

Disembark in Nauta, stopping at the Amazon Rescue Center on the drive to Iquitos. Fly to Lima for an overnight at the Wyndham Lima Airport Hotel. You may be able to take advantage of overnight flights home.

After breakfast, transfer to the airport in Lima for your flight home.