Southern Patagonian Ice Field in the context of Llanquihue glaciation

An ice field (also spelled icefield) is a mass of interconnected valley glaciers (also called mountain glaciers or alpine glaciers) on a mountain mass with protruding rock ridges or summits. They are often found in the colder climates and higher altitudes of the world where there is sufficient precipitation for them to form. The higher peaks of the underlying mountain rock that protrude through the icefields are known as nunataks. Ice fields are larger than alpine glaciers, but smaller than ice caps and ice sheets. The topography of ice fields is determined by the shape of the surrounding landforms, while ice caps have their own forms overriding underlying shapes.

The Southern Patagonian ice field dispute is a border dispute between Argentina and Chile over the delineation of the boundary line between the two countries on the Southern Patagonian Ice Field, a large expanse of glaciers located in the Patagonian Andes, which is the largest non-polar continental ice field with land access. It is called continental ice in Argentina and southern ice field in Chile, to differentiate it from the northern ice field. As of 2025, the Argentine–Chilean border in this sector is still pending of definition according to the 1998 agreement signed by both countries. The original border was defined 100 years prior on 1 October 1898 by experts from both countries.

The Patagonian Ice Sheet was a large elongated and narrow ice sheet centered in the southern Andes that existed during the Llanquihue glaciation. The ice sheet covered all of Chile south of Puerto Montt plus the western fringes of Argentine Patagonia.

The ice sheet extended beyond the crest of the Andes into Argentina, but because of the dryness of the climate it did not reach beyond present-day lakes such as the Yagagtoo, Musters, and Colhue Huapi. At its peak (about 18,000 to 17,500 years ago), the Patagonian Ice Sheet covered about 480,000 km of land with an estimated ice-volume of more than 500,000 km, of which about 4% remains glaciated today in two separated portions known as the Northern and Southern Patagonian Ice Fields.

The Perito Moreno (Spanish: Glaciar Perito Moreno), Francisco Gormaz or Bismarck Glacier is a glacier located in Los Glaciares National Park in southwest Santa Cruz Province, Argentina, and originated in the Magallanes Region in Chile, being also part of the Bernardo O'Higgins National Park. It is one of the most important tourist attractions in the Argentine Patagonia.

The 250 km (97 sq mi) ice formation, 30 km (19 mi) in length, is one of 48 glaciers fed by the Southern Patagonian Ice Field located in the Andes system shared with Chile which has a small part of the origins of the glacier. This ice field is the world's third largest reserve of fresh water.

The Aysén del General Carlos Ibáñez del Campo Region (Spanish: Región de Aysén, pronounced [ajˈsen], or Región de Aysén del General Carlos Ibáñez del Campo), often shortened to Aysén Region or Aisén, is one of Chile's 16 first order administrative divisions. Although the third largest in area, the region is Chile's most sparsely populated region with a population of 102,317 as of 2017. The capital of the region is Coyhaique, the region's former namesake. The region's current namesake is the former President of Chile, General Carlos Ibáñez del Campo.

The landscape is marked by several glaciations that formed many lakes, channels and fjords. The region contains icefields including the Northern Patagonian Ice Field and the Southern Patagonian Ice Field, the world's third largest after those in Antarctica and Greenland. The northern half of the region feature a north-south string of volcanoes. While the western part of the region is densely vegetated and mountainous, the eastern reaches contain open grasslands and much flat and rolling terrain.

The Upsala Glacier is a large valley glacier on the eastern side of the Southern Patagonian Ice Field. Its higher portion lies in a disputed territory between Chile and Argentina. While the glacier flows from north to south it has three lesser eastflowing tributary glacier: Bertacchi, Cono and Murallón.

The glacier terminus is at Upsala channel of Lago Argentino. The Upsala Glacier is well known for its rapid retreat, which Greenpeace cites as evidence for global warming. Its retreat has been ongoing since the glacier was first documented in 1810.

The Zona Austral (Southernmost Zone) is one of the five natural regions into which CORFO divided continental Chile in 1950 corresponding to the Chilean portion of Patagonia. It is surrounded by the Zona Sur and the Chacao Channel to the north, the Pacific Ocean and Drake's Passage to the south and west, and the Andean mountains and Argentina to the east. If excluding Chiloé Archipelago, Zona Austral covers all of Chilean Patagonia.