The Guadarrama mountain range (Sistema Central) contains some ecologically valuable areas, located in the Community of Madrid and Castile and León (provinces of Segovia and Ávila).

Altogether there are more than 1,280 different species in the zone declared a national park, of which 13 are in danger of extinction, more than 1,500 native plants and 30 different types of vegetation.

The autonomous community of Castile and León agreed in principle to the inclusion of part of its territory in the proposed national park, but delays in creating the corresponding plan made it appear in early 2008 that the project was being put aside.

However, in 2009 Castile and León indicated it would approve a plan for the national park in 2010, albeit a scaled-down version, and this timetable was adhered to.

More detailed proposals were produced in 2009, and received a positive response from the municipios affected, which welcomed the scope for increased urbanisation.