The Perito Moreno Glacier () is a glacier located in Los Glaciares National Park in southwest Santa Cruz Province, Argentina. It is one of the most important tourist attractions in the Argentine Patagonia. The ice formation, 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 Perito Moreno Glacier, located from El Calafate, was named after the explorer Francisco Moreno, a pioneer who studied the region in the 19th century and played a major role in defending the territory of Argentina in the conflict surrounding the international border dispute with Chile. Status Despite most of the innumerable glaciers worldwide retreating, one of the few unusual glaciers that maintains in a state of equilibrium is the Perito Moreno Glacier because it continues to accumulate mass at a rate similar to that of its loss. The reason remains debated by glaciologists. The terminus of the Perito Moreno Glacier is wide, with an average height of above the surface of the water of Argentino Lake, in Argentina. It has a total ice depth of . History In 1879, the British Chilean Navy captain, Juan Tomás Rogers, was the first non-indigenous person to sight the majestic glacier which he named "Francisco Gormaz", after the Director of the Hydrographic Office of the Chilean Navy, sponsoring organization of the discovering expedition. Some years later, Rudolph Hauthal, attached to the Argentine Boundary Commission, saw the glacier and decided to name it "Bismarck" in honor of the Prussian Chancellor. In 1881, the Boundary Treaty between Chile and Argentina was signed, which defined the boundaries of both countries in the Andes mountain range up to the 52nd parallel. The glacier is east of the Andes Mountains and empties into Lake Argentino, which also is under Argentine sovereignty. Before the treaty, the area was in dispute between both countries. Finally, in 1899, after long years of research, compilation of archaeological material, and surveys of the area, Lieutenant Iglesias, who was in charge of the studies for the Argentine Hydrographic Institute, named the glacier Perito Moreno in homage to Francisco Moreno. Rupture Pressure from the weight of the ice slowly pushes the glacier over the inner fjord of Lake Argentino reaching the coast of Península