The Purus National Forest covers 256,000 hectares of dense Amazon rainforest in the municipality of Pauini, in the Brazilian state of Amazonas. It runs along the west bank of the Purus River, downstream from Boca do Acre. The boundaries are drawn in a way that is unusual for a Brazilian protected area: the forest wraps around an inhabited village rather than excluding human settlement. Ceu do Mapia sits near the middle, connected to the wider world by a single winding stream. Around six hundred people lived there as of 2010, practicing subsistence agriculture, raising small animals, and managing a community forest plot of 1,400 hectares. In a region where national forests usually mean timber concessions or cattle pressure, this one is arranged around a spiritual community.

Ceu do Mapia is the international heart of Santo Daime, a religion that blends Catholic Christianity with practices from Afro-Brazilian traditions and indigenous Amazonian plant medicine. At its center is a tea brewed from two rainforest plants - the ayahuasca vine and the chacruna leaf - drunk as a sacrament in ceremonies that can last all night. The religion was founded in the 1930s by Raimundo Irineu Serra, a rubber tapper in Acre who became known as Mestre Irineu. After his death his followers established Ceu do Mapia in the mid-1980s as a place where the tradition could develop on its own land. Today Santo Daime churches operate across Brazil and in several other countries. The village in the forest is where it all refers back to: a pilgrimage site for adherents, a working community for residents, and a test case for whether a religion built around a jungle plant can survive without the jungle surrounding it.

The ecosystem around the village is worth the trip on its own. The canopy reaches fifty meters in the terra firme uplands - areas above the floodplain - sustained by trees like the Brazil nut (Bertholletia excelsa), the massive Dinizia excelsa, and various Anacardium species. Along the Mapia stream itself, the varzea forest of seasonally-flooded lowland is denser and lower, topping out around twenty meters. The alluvial soils here are fertile thanks to sediment washed down from the Andes. Step uphill and the soils turn poor and acidic, typical of the old Amazon basin. Temperatures range from 22 degrees on cool nights to the upper twenties on hot afternoons. Rainfall averages 1,750 millimeters or more per year, most of it falling between October and April.

The Purus National Forest was created by federal decree on 21 June 1988, and is classified as IUCN category VI - a protected area managed for sustainable use. The Chico Mendes Institute for Biodiversity Conservation administers it. In 2005 the federal colonization agency recognized the forest as supporting 200 families of small producers eligible for agricultural credit; by 2008 that number had been raised to 300. A management plan was approved in 2009 and a consultative council formed in 2010. In 2007, residents began working with the Federal University of Vicosa and the Rio de Janeiro Botanical Garden on community forest management - a plan to harvest enough wood for local construction needs without converting the forest into timberland. The logging plot is limited to 100 hectares per year.

The forest doesn't exist in isolation. The Inauini/Teuini Indigenous Territory overlaps parts of its northern boundary; the Mapia-Inauini National Forest sits immediately to the west; the Camicua Indigenous Territory adjoins the south. Together these protected areas form a continuous block of rainforest in a part of Brazil where deforestation pressures are heavy. Along the Mapia stream, closer to the village, some forest clearing has already happened. Further back - beyond the village, past the Teuini tributary - the forest is still largely intact. From the air, the Purus National Forest reads as one of those places where the map is drawn carefully around communities that already knew where they wanted to live.