Characteristics: Thousands of years ago, glaciers covered a big part of the national park. These ice rivers eroded and gave shape to the landscape, excavating in the mountains large valleys. At the same time these ice rivers were fragmenting and dragging lot of rocks, which had been accumulated in the front and the sides of the glacier, making small hills called “morrenas”. In a later climate change, which included a temperature increase, caused the reduction of the surface occupied by ice. Large milky water lakes occupied the bottom of the valleys and lush forests covered their slopes.
The ice countryside occupied an approximate surface of 2.600 km2 (a 30 % of the surface is covered by ice). From there, 47 bigger glaciers descend. The most famous glacier is the Perito Moreno, which expands over the south side of the Argentino Lake waters, with a 5 km front and 60 metres high over the lake.
Upsala glacier, which is ubicated in the north side of the same lake, is the bigger one, with 50 km length and almost 10 km wide.
In the north side of the PN Los Glaciares (Los Glaciares National Park) there is the Fitz Roy, which stands up for its length (3.376 metres) and its huge aspect: a surrounding “cordillerana” mountain chain environment.