The vascular flora of the National Park and its Peripheral Protection Zone includes about 1680 subspecific or specific taxa range. Due to its status, as a remarkable altitude massif, to its continental character in relation to other Central System massifs that will surround it, The Sierra de Guadarrama is a singular area with high floristic diversity in the Iberian Peninsula. It is in addition, a representative area of the flora and vegetation of the Mediterranean high mountain ecosystems. Within the territory, the Peñalara Massif and El Paular Valley should be noted for their uniqueness and high levels of diversity.
Taking into account biogeographic criteria, on endemicity, restricted distribution, or inclusion in protection catalogs (Spanish Catalog of Threatened Species, Madrid Regional Catalog of Endangered Species, Castilla y Leon Protected Flora, Red List of Spanish Vascular Flora), it has been established the National Park and the Peripheral Protection Zone rare, endemic and threatened vascular flora. This set of taxa is formed by some 446 species. Approximately one fith of these species, have been considered high value for the following reasons: they are very localized, are classified as extinction risk at the level of the Regional Catalog of Endangered Species in the Community of Madrid, they are present in the Red List of Spanish Vascular Flora, or are Central System endemism.
With this project, a mapping of all these species is being carried out, by determining their presence or absence in UTM grid 1 x1 Km throughout the National Park and its Peripheral Protection Zone. The results obtained in will be used to define, from the floristic point of view, particularly sensitive areas, on which will apply certain management measures.
A work on specific plans for its follow up is being carried out, on the basis of this information on the rare, endemic or threatened flora.