Sangay

Declared in 1975 and a UNESCO World Heritage Site since 1983, Sangay preserves an unbroken ecological transition from lowland Amazon rainforest up to the glaciers of three volcanoes — Sangay, Tungurahua and El Altar — with barely any human intervention across much of its extent, which UNESCO singles out as an exceptional case of complete altitudinal connectivity. Sangay itself is one of the most active volcanoes in Ecuador, in near-continuous eruption for decades, while neighbouring El Altar is in fact a collapsed ancient caldera whose remains form a spectacular crown of nine peaks around a central lake.