The National Park extends over the Sierra de Guadarrama mountain range, whose highest peak is the Peñalara summit. Other outstanding features include the Puerto de Navafría pass and the La Morcuera and Siete Picos mountain ranges.
All these mountainous areas are much frequented by hiking and climbing enthusiasts. The cooler and more humid conditions to be found in these mountains, plus the fact that it is so little affected by human activity, have made these mountains an exceptional refuge for biodiversity. Its physical features include glacial cirques and lakes, and granite rock fields, and its plant landscapes are formed by high-mountain ecosystems and extensive forests of Scots pine.