Maipo is a stratovolcano

Stratovolcano

A stratovolcano, also known as a composite volcano, is a tall, conical volcano built up by many layers of hardened lava, tephra, pumice, and volcanic ash. Unlike shield volcanoes, stratovolcanoes are characterized by a steep profile and periodic, explosive eruptions...

 in the Andes

Andes

The Andes is the world's longest continental mountain range. It is a continual range of highlands along the western coast of South America. This range is about long, about to wide , and of an average height of about .Along its length, the Andes is split into several ranges, which are separated...

, lying on the border between Argentina

Argentina

Argentina , officially the Argentine Republic , is the second largest country in South America by land area, after Brazil. It is constituted as a federation of 23 provinces and an autonomous city, Buenos Aires...

 and Chile

Chile

Chile ,officially the Republic of Chile , is a country in South America occupying a long, narrow coastal strip between the Andes mountains to the east and the Pacific Ocean to the west. It borders Peru to the north, Bolivia to the northeast, Argentina to the east, and the Drake Passage in the far...

. It is located 90 km (55.9 mi) south of Tupungato

Tupungato

Tupungato, one of the highest mountains in South America, is a massive stratovolcano dating to Pleistocene times. It lies on the border between the Chilean Metropolitan Region and the , near a major international highway about 80 km east of Santiago, Chile. It is located about south of Monte...

 and about 100 km (62.1 mi) southeast of Santiago

Santiago, Chile

Santiago , also known as Santiago de Chile, is the capital and largest city of Chile, and the center of its largest conurbation . It is located in the country's central valley, at an elevation of above mean sea level...

.

Maipo retains a symmetrical, conical volcanic shape, unlike many of the other nearby peaks, making it the best known peak in the region, though it is not the highest. (Nearby Castillo is 5,485 m high.) Maipo is also almost the southernmost 5,000 metre peak in the Andes. (That honor goes to Sosneado, about 50 km to the south).

Maipo is located within the Diamante Caldera, a feature of about 15 km by 20 km size that is about one-half million years old. It rises about 1,900 m (6,230 ft) above the floor of the caldera. Immediately to the east of the peak, on the eastern side of the caldera floor, is Laguna del Diamante

Laguna del Diamante

Laguna del Diamante is a lake located in the province of Mendoza, Argentina, in the San Carlos Department, some 198 km from Mendoza. It covers a surface area of about 14.1 km² and is one of the largest freshwater resources in the Province. Nearby is Maipo volcano...

, a picturesque lake that formed when lava flows blocked drainage channels from the caldera in 1826. The Diamante Caldera erupted 450 cubic kilometres (108 cu mi) of tephra, 450 ka.

The region's climate is transitional between the drier Mediterranean climate of the peaks to the north and the cold, moist climate of Chilean Patagonia

Patagonia

Patagonia is a region located in Argentina and Chile, integrating the southernmost section of the Andes mountains to the southwest towards the Pacific ocean and from the east of the cordillera to the valleys it follows south through Colorado River towards Carmen de Patagones in the Atlantic Ocean...

. Hence, while less glaciated than Patagonia, it has more permanent snow (on the wet, Chilean side) than peaks of similar elevation to the north.