The inactive
stratovolcano Chimborazo (
Spanish pronunciation&_160;[t?imbo'?aso]) is
Ecuador's highest summit. Its last eruption is thought to have occurred some time in the first millennium AD. Its summit is generally regarded as the spot on the surface farthest from the centre of the Earth (since the Earth is not a perfect
sphere), a distance of 6,384.4&_160;km (3,968&_160;mi).
Chimborazo is located in the Cordillera Occidental of the Andes of central Ecuador, 150&_160;km (93&_160;mi) south-southwest of the capital Quito. It is a neighbour to 5,018&_160;m high Carihuairazo. Chimborazo's majestic summit rises 2,500&_160;m above the surrounding highlands (~3,500 to 4,000 m) with a ~20&_160;km wide base.
Under clear conditions the summit of Chimborazo can be seen from the coastal city Guayaquil, nearly 140&_160;km away. The nearest cities are Riobamba (~30&_160;km to the southeast), Ambato (~30&_160;km to the northeast) and Guaranda (~25&_160;km to the southwest). Chimborazo is surrounded by the Reserva de Produccion Faunistica Chimborazo which forms a protected ecosystem to preserve the habitat for the Andes native camelids vicuña, llama and alpaca.
The top of Chimborazo is completely covered by glaciers, with some north-eastern glacier arms flowing down to 4,600 m. Its glacier is the source of water for the population of the Bolivar and Chimborazo provinces of Ecuador. Chimborazo glacier's ice mass has decreased over the past decades due to the combined influences of global warming, ash covers from recent volcanic activity[note 2] of Tungurahua, and the El Niño phenomenon.[6][7]
