Sangay (phoenetic: sang [ai] or sang-eye) is the most continuously active volcano in the world and the most hardcore mountain in Ecuador to climb because of the demanding nature of the approach and the prevailing appalling weather.

Different interpretations for the name of the mountain exist. Some say it is from the Quichua word samkay, meaning “to frighten, scare, or terrorize”; others, primarily people living in the east, say it is from the word shanga, meaning ‘good-natured.” The reason for this wide disparity is that despite Sangay’s high level of activity, it has not damaged any of the surrounding areas.

The isolated Sangay volcano, located east of the Andean crest, is the southernmost of Ecuador’s volcanoes, and its most active. The dominantly andesitic volcano has been in frequent eruption for the past several centuries. The steep-sided, 5230-m-high glacier-covered volcano grew within horseshoe-shaped calderas of two previous edifices, which were destroyed by collapse to the east, producing large debris avalanches that reached the Amazonian lowlands. The modern edifice dates back to at least 14,000 years ago. Sangay towers above the tropical jungle on the east side; on the other sides flat plains of ash from the volcano have been sculpted by heavy rains into steep-walled canyons up to 600 m deep. The earliest report of a historical eruption was in 1628. More or less continuous eruptions were reported from 1728 until 1916, and again from 1934 to the present. The more or less constant eruptive activity has caused frequent changes to the morphology of the summit crater complex.

Photo by Minard Hall, 1976 (Escuela Politécnica Nacional, Quito).