The 250 km2 (97 sq mi) ice formation, and 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. This icefield is the world's third largest reserve of fresh water.
The Perito Moreno Glacier is one of only three Patagonian glaciers that is growing. The reason remains debated by glaciologists. The terminus of the Perito Moreno Glacier is 5 kilometres (3 mi) wide, with an average height of 74 m (240 ft) above the surface of the water of Lake Argentino, in Argentina. It has a total ice depth of 170 metres (558 ft).