Valsain Mountains
The environmental richness is very high as this is an area of little human activity and historically protected as a reserve and hunting ground by the Spanish monarchy.
The valley and the mountains are crossed by the CL-601 regional road that connects Segovia with Madrid through the Navacerrada pass.
Another series of asphalted roads and highways (in different states of preservation) cross the area too; they are usually closed to vehicular traffic.
Like the rest of the Sistema Central, the materials that form the soil of the valley in which the Valsain Mountains are located are of granite and gneiss origin.
The main water courses that run through the Valsain Valley—and with it its mountains—are the rivers Eresma, Acebeda and Peces, all of them in the upper part of their basins.
These rivers are formed by the sum of a multitude of small streams that flow down from the mountains surrounding the valley.
The Acebeda river is formed by the waters that flow down the slopes of Montón de Trigo and La Pinareja.
The predominant tree species of this area is the pinus sylvestris or Scots pine, that occupies the upper part of the mountains, above 1200 meters.
On the banks of the rivers there are formations of gallery forests, and we can also find holly, yew, poplar, sour cherry, ash and maple trees, which are combined with the shrubs and bushes such as broom, rock rose steppe, juniper, and heather.
The undergrowth of the pine forests is usually composed of oak (Quercus pyrenaica, this below 1400 masl) and retama, juniper, broom, and brambles.
And in the lower parts, retamas, rowan, blackthorn, hawthorn, heather, hazel, cherry and holly.
The black vulture (Aegypus monachus) and specimens of imperial eagle (Aquila adalberti) stand out for their numbers.
Among the bats: Myotis blythii nathalinae is an Iberian endemism, as are Sorex granarius, Talpa caeca occidentalis and Microtus lusitanicus depressus (Pitymys) .
Among the more than 570 species of insects, we can find the emblematic greater stag beetle (Lucanus cervus) and the butterflies Graellsia isabelae, Parnassius apollo, Leptidea sinapis and Boloria selene castellana.
The opening of the Valsain forests for the enjoyment and relaxation of the citizens also seeks to disseminate the natural values among the population.
The activity generated around the Valsain Mountains has a very significant influence on the environment and on the municipality of Real Sitio de San Ildefonso.
Aimed at the enjoyment of the mountains by the general public and the dissemination of natural values, three recreational areas have been set up.
In the Boca del Asno area, there is an Interpretation Center,[1] opened in 2004, which brings the mountains closer to visitors by showing their history, natural wealth and management.
The center is structured in six parts: A system of guided routes—free service—intends to disseminate the natural values and knowledge of the terrain.
The facilities of the Centro Nacional de Educación Ambiental (the CENEAM) are located within the lands occupied by the Valsain Mountains.
The center consists of several facilities among which the projection of a slideshow about life in the mountains during the seasons of the year stands out.
There are several rooms showing the different peculiarities of the Valsain Valley and the Guadarrama mountain range, which are complemented by an interactive walk through the pine forest surrounding the facilities.
(Translation: Mountains must be managed in a sustainable manner, integrating environmental aspects with economic, social and cultural activities in order to conserve the natural environment while generating employment and collaborating to increase the quality of life and development expectations of the population.
)[2]To achieve these objectives, the area of the Valsain forests is divided into different zones or quarters, in which lines of action are established depending on their characteristics.
[3] In the pine forest, thinning is carried out successively by coppicing in order to replace mature trees with younger ones.
These activities are limited in terms of the way and time of cutting, in certain areas, for different reasons such as landscaping, non-interference in the awnings and headlands or in the reproduction of protected species.
The felling is done by cutting with a chainsaw, then the pines are removed from the forest with different means (horses, tractors or loaders) and are transported and stacked with crane trucks after being measured.
At the beginning, the mass of young pines is very dense and decreases by natural process and by human intervention that performs different cleanings and cuts until reaching the convenient density for an optimal development of the tree.
In areas of special protection, where some endangered species live, no intervention is carried out in order to preserve the structure of the "tree canopy" and not to disturb with the movement of men and machines.
