Alpine communities in central Spain are found at the top of the Sistema Central, an east-west running mountain range consisting of different mountain chains. These communities grow in a somewhat reduced space, at altitudes of over 2,000 metres; the summits in this range are always below 2,300 - 2,350 metres, except Almanzor (2,592 metres), Peñalara (2,429 metres) and El Calvitero (2,401 metres) among others. The threats affecting conservation of alpine biodiversity are mainly related to the influence of big cities such as Madrid, the third most populous city in Europe with over three million inhabitants and more than six million in the Greater Madrid Area. The city is only 60 kilometres from the Sierra de Guadarrama, one of the mountain ranges in the Sistema Central. There are other smaller cities such as Ávila and Segovia with populations of approximately 50,000 which are also located very near the Sistema Central mountains. They exert an influence on the landscape similar to Madrid and there are similarities in their use of mountain resources.
