Iquitos is the seat of Maynas, and it is the most unusual regional capital in South America. With more than 400,000 residents, it is the largest city in the world that cannot be reached by road - you arrive by river or by air, and there are no other options. The Amazon, the Itaya, and the Nanay rivers converge here, and Iquitos rose on their banks during the rubber boom of the late nineteenth century, when barons built European-style mansions in the jungle and imported tilework from Portugal to decorate them. The Casa de Fierro, an iron house designed in the workshop of Gustave Eiffel, still stands on the main plaza, rust-stained and strange, a relic of the moment when Amazonian latex made a small number of men astonishingly rich.

Maynas is divided into eleven districts, each with its own mayor and its own stretch of rainforest. Some of their names are places most Peruvians have never seen. Torres Causana, with its capital at Pantoja, lies up the Napo River near the Ecuadorian border. Las Amazonas, named for the river, has its seat at a settlement called Francisco de Orellana - after the conquistador who in 1541 became the first European to float the full length of the Amazon from the Andes to the Atlantic. Napo district, capital Santa Clotilde, stretches northward toward the border with no road connecting it to the rest of the country. Most districts are reachable only by boat, though small aircraft can land at a few gravel strips when the weather cooperates.

Ninety-six percent of Maynas residents speak Spanish at home, but the language map hides a more complex reality. The indigenous languages of the Peruvian Amazon - Kukama-Kukamiria, Yagua, Bora, Huitoto, Matses, and dozens of others - are spoken by minorities who have seen their populations shrink through disease, displacement, and the erasure that comes when schools teach only in Spanish. Quechua, originally a highland language, is spoken by 2 percent, often by migrants from the Andes. Smaller pockets of Aymara speakers appear in the statistics. Efforts to preserve the local Amazonian languages have gained traction in recent decades through indigenous radio stations, bilingual schools, and community storytelling projects. The languages carry knowledge that Spanish-language science is only now beginning to document.

The General Command of Maynas was created by the Spanish crown in 1802 to administer these remote territories from Quito, but in 1822 the government of the newly independent Peru declared the province part of its territory. Joaquin Mosquera traveled from Colombia that same year to demand its return. The demand failed. On July 25, 1824, Gran Colombia's congress passed a law incorporating Maynas, Jaen, and Matamoros into its departments. Peru refused to withdraw. Tensions escalated into the Gran Colombia-Peru War of 1828 to 1829. The war settled little on the ground but much on paper: Peru kept Maynas. The border with Ecuador remained contested, flaring repeatedly, most seriously in the Cenepa War of 1995, until the Itamaraty Peace Declaration of 1998 finally drew a definitive line.

Maynas bounds Ecuador to the northwest and Colombia to the north and northeast - a three-nation rainforest that knows no border on the ground. The province sits in the western Amazon, where the rivers flood seasonally and entire neighborhoods of Iquitos sit on stilts or floating platforms that rise and fall with the water. Belen, a district that is effectively a floating town, becomes accessible by canoe during high water. The Allpahuayo-Mishana National Reserve, south of the city, protects white-sand forests unique to this patch of the Amazon basin, where isolated soils have produced bird and plant species found nowhere else on Earth. More than half of Maynas residents are under twenty. The population is growing. The forest, under pressure from logging and extraction, is not.