Sangay is one of two active volcanoes located within the namesake Sangay National Park, the other being Tungurahua to the north. As such it has been listed as a UNESCO World Heritage Site since 1983. The area's isolation has allowed it to maintain a pristine ecology relatively untouched by human interaction, and the park hosts a biome ranging from alpine glaciers on the volcanoes' peaks to tropical forest on their flanks. Altitude and rainfall are the most significant local factors affecting fauna, and therefore the most lush ecosystems are found on the wetter parts of the volcano's eastern slope.