The transition zone between dry highlands and humid lowlands, the Yungas is where the Andes falls away into the Amazon Basin. Above the steaming, forested depths rise the near-vertical slopes of the Cordillera Real and the Cordillera Quimsa Cruz, which halt altiplano-bound clouds, causing them to deposit bounteous rainfall. Vegetation is abundant, and tropical fruit, coffee, coca, cacao and tobacco grow with minimal tending.
The Yungas is composed of two provinces in La Paz department – Nor and Sud Yungas (oddly, most of Sud Yungas lies well to the north of Nor Yungas) – as well as parts of other provinces. Coroico and Chulumani are the main population centers. Most people here claim Aymará descent but there is also a noticeable Afro-Bolivian population. Visitors often find locals to be more friendly here than in the colder altiplano (must be the heat).