Only from Cerro Colorado – a rocky outcrop that rears vertiginously over the treetops – is it possible to make out the vastness of the Gran Chaco as it stretches from this corner of Bolivia beyond the horizon into Paraguay. This enormous swath of dry forest and scrubland, where every plant or tree bears thorns, is South America’s second largest wilderness after the Amazon rainforest.
The Gran Chaco is threatened on all sides: Mennonite cattle ranchers have bought up large tracts in Paraguay and Brazilian farmers looking for cheap land for their soy crops have flooded across the border.
The quarter of it that lies in Bolivia is the best preserved, but even its habitats have been disrupted by a gas pipeline and military operations against drug traffickers, whose camps have been spotted in the 34,000 sq km (13,000 sq miles) of Kaa-Iya del Gran Chaco national park. Bigger than Belgium, it is Bolivia’s largest national park.