Lago Argentino is fed by four glaciers in all and the biggest by far is the Upsala Glacier, so named after the Swedish university which first commissioned a survey of the area in the early 1900s. Some 50 km long and 10 km wide, it is twice the length of Perito Moreno. The glacier is the longest in the Campo de Hielo Patagonico Sur (Southern Patagonia Icecap), the largest body of ice outside the poles, estimated to cover over 2,600 square kilometres, the major proportion of it being in Chile. Thirty per cent of the Los Glaciares National Park is covered by ice. Upsala ends in two separate frontages, each about four kilometres long and 60 metres high, although only one can be seen from Lago Argentino.