The Guadalix de la Sierra reservoir, which takes its name from the neighbouring village of Pedrezuela, dominates the landscape of the municipality and forms part of the Natura 2000 Network. It is recognised by experts and enthusiasts as one of the best places to observe aquatic birds in the Community of Madrid.

Among the inhabitants of this bird paradise fed by the Guadalix river, we find several varieties of ducks, ducks, coots, herons, cormorants and many others that delight birdwatchers and laymen alike, as well as countless storks that are no less beautiful for being more commonplace.

The reservoir is an essential wintering spot for birds, as well as a desired resting and refuelling stop for migratory birds. Its large shallow water surface favours the vegetation that gives them protection and food. Several paths allow us to go around it comfortably and safely, including the historic Camino Mendocino along the reservoir.

For decades, the reservoir has also had a yacht club, whose facilities and activities allow us to approach the world of water with pleasure and safety. Sailing, kayaking, windsurfing and paddlesurfing are the main modalities that invite us to learn them and enjoy this body of water.

A large mirror from which to contemplate another view of the Sierra de Guadarrama mountain range on its slopes from the high passes of Canencia and La Morcuera, before diving into the streets of this village to recover our strength. In them awaits the surprise of its cinematographic history, thanks to the shooting in 1953 of the film "Bienvenido Míster Marshall" by Luis García Berlanga, an interesting past also ready to be discovered.