Serra do Divisor National Park

Serra do Divisor takes its name from the low sandstone range that forms the watershed between the Amazon basins of Brazil and Peru, and the park runs along the border in the far west of Acre. The relief matters: most of Brazilian Amazonia is flat, and these ridges rising to about six hundred metres create the altitude gradients that account for the extraordinary species counts recorded here, including plants and birds found on the Andean side and nowhere else in Brazil. There are cold-water streams, small waterfalls and sulphur springs. The park is also one of the least visited in the country - reaching it means flying to Cruzeiro do Sul, driving to Mancio Lima and then travelling by boat, and there is essentially no infrastructure once you are inside.

What you actually see

• The Brazil-Peru watershed - the sandstone ridge that divides the two Amazon drainages.
• Relief in a flat basin - hills to six hundred metres, rare in Brazilian Amazonia.
• Andean-edge species - plants and birds otherwise absent from Brazil.
• Cold streams and sulphur springs - the water features along the ridge base.

When to go

June to September, the drier months. Four days.

Honest expectations

This is among the hardest parks in Brazil to reach: a flight, a road and a long boat journey. Permits and guides are required, there are no facilities, and rain can strand a trip. Costs are high for what is a wilderness visit, not a sightseeing one.

Nearby

Cruzeiro do Sul is the regional hub; the Peruvian border is west along the ridge.