It is an Autonomous Community formed by one province, that includes from the western spurs of the Central Mountain chain up to the Tagus valley, occupying a surface of 8.028 km2.

It occupies the geographical center of the peninsula and is very determined by the capital Madrid.

With the provincial division in 1833 the provincial limits were established, joining municipalities that were depending on Guadalajara (Buitrago), on Segovia (Lozoya's valley) and others on Toledo and Avila. These limits remain in the current autonomic ones.

We can find landscapes with shaped granitic in the Central System, as The Pedriza of the Manzanares, landscapes with shaped glacier in the Guadarrama mountain range, around Peñalara's lagoon, zone that was affected by the glaciations of the Riss and the Würm. In the southern areas of the province we find also clayey and marly landscapes.

The most important relief units are Gredos's mountain range and that of Guadarrama, inside the Central System, formed by horst and graben, on hard materials and silica, as granites, gneis, slates, etc., and the Tagus depression, on soft and clayey materials.

The zone among the mountain ranges and the depression is a transition zone or piedemonte, formed by sandy materials, proceeding from the mountain range.

It predominates the continental Mediterranean climate, with the exceptions of the high mountain. The summers are very warm and very cold winters, with frequent frosts and skies without clouds. Both stations are very long, so that the autumn and the spring are not obvious. The maximum rainfall is given in November and in April and the minimum in July and August. The snowfalls are frequent in the mountain range.

The traffic, the heatings and the urban life of Madrid agglomeration have created an urban microclimate that has provoked a heat island, which can have 4ºC more than the adjacent areas.

Only in the mountain range a significant vegetation remains. We prune finding there forests of pines, oaks, chestnut-trees, hazels, mufflers, hollies and one of the most southern beeches forest of Spain, which is located in the Montejo's municipal term of the mountain range, a natural protected space. The junipers and the pastures are approximately over all 1.900 meters.

The rivers Jarama, Guadarrama and Alberche, tributaries of the Tagus, and the Arroyo del Puerto, tributary of the Douro, form the fluvial principal net of the Autonomous Community. The river Jarama is the most important, with tributaries as the Lozoya, the Guadalix, the Henares, the Manzanares and the Tajuña. It constitutes the most important hydraulic reservation of the region, for the numerous reservoirs that exist on it.