The Perito Moreno Glacier (Spanish: Glaciar Perito Moreno) is a glacier located in the Los Glaciares National Park in southwest Santa Cruz Province, Argentina. It is one of the most important tourist attractions in the Argentinian Patagonia.
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 ice field is the world's third largest reserve of fresh water.
The glacier is unusual in that it is advancing, while most glaciers worldwide are retreating. The reason remains debated by glaciologists. The terminus of the Perito Moreno Glacier is 5 km (3.1 mi) wide, with an average height of 74 m (240 ft) above the surface of the water of Argentino Lake, in Argentina. It has a total ice depth of 170 metres (558 ft).