The National Park Aigüestortes and lake Sant Maurici is a protected natural area of the Lleida high Pyrenees. It is one of the twelve Spanish National Parks and the only one in Catalonia. It was declared a national park on October 21, 1955. It's located in the central part of the Sierra Pirenaica between the regions of Upper Ribagorça, Pallars Sobirá, Aran Valley and Pallars Jussá. The core of the park is in the municipalities of Valle de Boi and Espot. The geography of the park consists of high mountains because much of the land rises above 1.000 meters with peaks over 3.000 meters high. There is an abundance of quaternary glacial lakes. Two valleys stand out. In the west the valley with the characteristic Sant Nicolau river, its meadows and the meanders which are responsible for the name Aigüestortes, and in the east the valley of the Escrita river and Lake Sant Maurici. The steep slopes are a home to different ecosystems: grasslands, crops and deciduous forests at lower altitudes, evergreen forests higher up and meadows and high mountain rockeries on the highest levels. Thanks to the fact that for many years it has a protected status as well as for its natural inaccessibility, it has preserved its wild flora and fauna.