Noel Kempff Mercado

Declared in 1979 and later extended, it protects a sandstone plateau some 500 million years old on the Brazilian border, whose isolated form — sheer walls several hundred metres high setting it apart from the surrounding forest like an island on dry land — helped fire the imagination of early 20th-century writers about lost worlds with surviving prehistoric wildlife, in the literary tradition of Arthur Conan Doyle's The Lost World. It has been a UNESCO World Heritage Site since 2000 and, given how remote and hard to reach it is — several days of river and overland travel — it is among the least visited and best preserved national parks in the whole of South America.