Portal de Turismo de Castilla y León

Welcome to the Iruelas Valley "Las Cruceras" Nature Reserve Park House.

As in the rest of the houses of the park spread throughout the Castilla y León region, it is the recommended gateway to these natural areas. At this interpretation centre, the educators will inform you about the Nature Reserve and help you plan your visit.

Here, information on emblematic species and habitats is provided to facilitate the identification and highlight the cultural and natural heritage of these places, in a respectful manner and promoting the conservation and appreciation of biodiversity and cultural heritage.

The Park House located in Iruelas Valley Nature Reserve, also known as "Las Cruceras." It is located at the old Iruelas Valley resin mill, where the resin from pine trees was brought in the past to be processed. The entire fenced enclosure is considered part of the House, the reception building being the one in front of the entrance. The buildings have been refurbished, maintaining the existing structure and spaces, which is why the buildings have an industrial feel.

The Iruelas Valley was declared a Nature Reserve in 1997 and focuses on the protection of the black vulture, the largest bird of prey in Europe with a wingspan of almost three metres. This valley is home to the most significant population in Castilla y León, with around 150 pairs registered in the last census.

The Iruelas Valley is located in the province of Ávila. It belongs to the Central System Mountain Range, more specifically to the eastern massif of the Gredos Mountains, on the right side of the Alberche River and the catchment area of the Burguillo Reservoir. Despite its small size, only 8828 hectares, this natural space is characterised by its unique orography, which favours a range of orientations and exposures that create microclimates, capable of hosting a very varied vegetation that contrasts with the rocky peaks and small snowfields.

Enter the house and you will discover a pillar with screens, the reception desk, display cabinets, and the green shop, where you can purchase a souvenir of your visit.

If you are looking for more information, you can go to the reception area where the educators offer free information about the Nature Reserve, its location, the reasons why the Iruelas Valley has been protected, what you can do and visit, even where you can eat or what routes you can take. This welcome is usually done next to the pillar on the left, next to the photographer and in front of the sign with information on the location of the Park House, within the network of natural spaces of Castilla y León.

At the end of the room, you will find the temporary exhibition hall where you’ll discover a documentation centre, where you can read any of the books on the shelves.

To the right of the room, you can find monitors showing videos of the black vulture and the Iberian imperial eagle, two of the Nature Reserve's most emblematic birds. You can also find feathers and pictures showing the difference between black vultures, griffon vultures, and bearded vultures.

The black vulture has a mostly brown plumage with dark shades on the back, highlighting a featherless neck and part of the head, although with some black down on the face and crown. Its beak boasts a bluish-purple hue with a black tip. Like most vultures, the black vulture hovers in the air and rarely flaps its wings, keeping its head back and wings spread, using its tail as a rudder. Its habitat includes rocky crags and ravines with abundant vegetation, preferring areas of Mediterranean forest. This vulture tends to live in loose colonies and rarely migrates.

Return to reception and go outside to visit the House's facilities.

The "Las Cruceras" house was the old resin mill in the area. Here, resin from the nearby pine forests was processed.

In the porch, you can see the trunk of a resin pine tree and some posters with information about it.

Three species of pine stand out in the Iruelas Valley.

The first, the resin pine, is the most abundant and important. It is a medium-sized tree, 20 to 35 metres high, with orange-brown bark and an irregular top. The needles are thick and long, greenish blue to greenish yellow. The conical pine cones turn from green to reddish brown in 24 months, opening and widening.

The second, the black pine, is also a medium-sized tree, varying in height from 20 to 55 metres, with ash-white, brown to dark grey bark with grooves and plaques that crack with age. The needles, grouped in pairs, are strong, dark green in colour. This tree is remarkably long-lived, with specimens that can live up to 1000 years.

The last species, the Scots pine reaches a maximum height of 30 metres. Initially, its crown is conical, but as it matures, it becomes irregular and widens, with a trunk that changes from covered to bare. The needles are small, stiff and sharp, with a semi-circular shape, and serrated edges. This pine thrives in full sun, but does not tolerate shade. It prefers fertile, deep soils, but withstands drought and very cold winters.

In the garden, the three types of pines are planted and you can see the differences between them.

In the space before the house, next to the trunk of a resin pine, there are the pots in which the resin was collected, the wedge that was placed to direct the resin towards the pot and the three types of pine cones from the three types of pines.

The facilities of the site comprised the former resin factory. All the resin from the surrounding pine forests was brought here, where it was transformed and two by-products were obtained: a solid part, which is rosin; and a liquid part, which is turpentine. Turpentine was collected in two water tanks in the garden between the buildings.

Resin production was so important between 1936 and 1975 that houses were built for the resin and wood workers. Two settlements, Las Cruceras and La Rinconada, were built in this area. This product exuded slowly from man-made cuts to the pine trunks. It was collected in barrels and brought down in mules to the Las Cruceras distillery, where up to 50 families lived from exploiting the resin. The demand for labour and the exclusive dedication of the resin workers favoured the villages of Casillas and La Rinconada, the closest ones to the valley. Other traditional resources of the forest include timber, firewood, pasture for livestock, hunting and fishing, honey and mushrooms harvesting, which are still done today. Until 1990, all the wood cut in the valley was sent to the Las Cruceras sawmill.

These villages preserve examples of their past splendour, such as the 15th century church of El Barraco; the church and chapel of Our Lady of Mercy in San Juan de la Nava; the Baroque chapel of Anthony of Padua, the monastery of Los Jerónimos in El Tiemblo; the Crucero de San Marcos, the Romanesque bridge, and the church of Our Lady of Villares in Navaluenga.

In addition, this forest was one of the first in Spain to be ordered, back in 1886. Its excellent forest management has favoured the presence of numerous centenary pine trees, which are essential for maintaining a significant population of black vultures, as these large birds of prey nest in trees and need large treetops.

On the other side of the road, opposite the park house, was the old sawmill, where the wood was processed. Of this sawmill, only one saw remains, which is preserved in this garden.

Walk to a building containing the exhibition hall. To the right of this building, you can find another building with the toilets.

When you reach the exhibition hall, you will enter a rectangular room where you can find a map and two models of the Nature Reserve.

In the first model, you can see the limits of the Iruelas Valley marked with a brown cordon. The protected area of the Nature Reserve spreads over four villages: the one closest to this house and slightly larger is El Tiemblo, then there is El Barraco, San Juan de la Nava, and Navaluenga, which is located at the tail of the reservoir. These are the four villages whose municipal boundaries are within the protected area.

From the Park House, located on a peninsula of the reservoir, the Enebral route starts in an area full of junipers. The route goes down a wooden walkway, which can also be crossed on a wheelchair. The Iruelas gorge, which names the area, is marked on the model. At the end of the road that crosses Las Cruceras is the village of La Rinconada, which belongs to the municipality of El Barraco.

The whole forest of the Nature Reserve is an intense green, due to the pine forests, although the Castañar del Tiemblo is also a botanical jewel with centenary chestnut trees, including El Abuelo.

Chestnut trees are deciduous trees known for their fruits, the chestnuts. Their leaves are simple, bright green in summer and with warm tones in autumn. The bark is brown and greyish. The fruits are contained in spiny shells, known to many in the area as hedgehogs. Their presence in landscapes adds seasonal beauty and biodiversity.

To the right of the model, you can find the stairs, the lift, and a ramp that goes up against the wall.

The exhibition is presented by seasons.

In the centre of the room, there is a block where you can find the spring flora, with four samples of smells; some riddles, whose solution is behind the floodgates and the fauna and flora of the Iruelas Gorge.

In another part of the block are the gorges of the valley that feed the Burguillo Reservoir, although the main one is the Iruelas Gorge.

An otter, a frog, a trout, and birds such as the wagtail, the dipper, and the oriole are depicted.

The oriole is a bird distinguished by its striking bright yellow and black plumage, with distinctive contrasting colours. Medium-sized, with a slender silhouette and a pointed beak. This species is known for its characteristic song, which consists of a mixture of melodic notes and high-pitched squeaks. Orioles build hanging nests in the branches of tall trees.

Now, go up the ramp and after the second section, on the left, you will enter a room dedicated to the black vulture.

In the centre, there is a panel the same size as a black vulture, about 3 metres. Behind it, you’ll find four photographs: a pair of vultures, a vulture perched on the ground, a vulture arriving at a nest, and a vulture chick in the nest. If you look closely at the images, you will see that the male and female have no sexual dimorphism. They have identical plumage and at first glance it is impossible to distinguish their sex. In fact, scientists have to carry out tests to find out whether they are male or female.

Despite the name, black vultures have brown plumage, but they are so called because young birds have jet black feathers. Male and female are equally responsible for building the nest, incubating the egg, and raising and feeding the chick.

Now, you will find two hanging panels with the differences in feeding habits of the black vulture, the griffon vulture, the Egyptian vulture, and the bearded vulture.

The black vulture is noted for its robust beak, which it needs to break the skin of the carcasses it feeds from. Its role as a scavenger bird is very important, as it contributes healing and recycling nature. Vultures have a sturdy digestive system that prevents them from becoming infected and sick from eating animals that died from contagious diseases. This way, they manage to eliminate possible sources of infection that could be harmful to other creatures and people in the area.

The griffon vulture, unlike the black vulture, sticks its head into its prey to eat the entrails. Its neck is bare to prevent this area from becoming a source of infection due to the accumulation of food debris in the feathers.

The Egyptian Vulture, being the smallest of these birds of prey, shows remarkable intelligence. It uses tools to break ostrich eggs, throwing stones non-stop until the eggshell is broken. Did you know that the shell of ostrich eggs is so hard that it can support the weight of a person?

Finally, the bearded vulture is being reintroduced in the Sierra de Gredos by means of a 5-year programme. In the first year two specimens were introduced and in the following years, four or five. It is a very challenging programme, because it is a very territorial animal that only builds its nest in the place where it thinks it was born.

The following poster talks about the Iruelas Valley and the protection of the black vulture.

Leave the room and continue up the stairs. You will arrive to the summer section of the exhibit.

The main focus here is on the valley's Los Abuelos, or the Grandparents, with photos of some of the oldest trees in the Reserve: The "Grandfather" chestnut, with an estimated age of 500 years; the "Agujera" pine, which is 360 to 400 years old; and the valley yew that is 700 to 800 years old.

Another facet of the block is devoted to fauna: the bee-eater, the white-throated dipper, the European honey buzzard, and the imperial eagle. A zootrope simulates the flights of an imperial eagle and a common redstart.

The imperial eagle is a majestic bird of prey with a large wingspan and dark brown plumage. Its distinctive head is adorned with golden feathers. With broad wings and a long tail, this eagle is among the largest birds of prey. The imperial eagle feeds mainly on small mammals and birds, using its keen eyesight to locate prey from high altitudes.

On the other hand, the common redstart is a small bird noted for its characteristic plumage and active behaviour. Males have a bright orange tail, while the rest of the body has grey and black tones. It is known for its curious attitude and its ability to catch insects in flight, as well as its melodious and varied song.

If you go up to the next level, you’ll reach the autumn area. Here, we talk about the rutting of the deer, there are riddles, animal tracks, and the autumn colours of the forest.

Stag bellowing is a characteristic behaviour of male deer during the autumn rutting season. It consists of deep, resonant sounds, called "bellowing", which deer emit to attract females and demonstrate territorial dominance, accompanied by physical displays such as antler rubbing and ground marking.

The last side of the block presents the soil as a large recycling plant, where millipedes, earthworms, mites, springtails, and other small animals shred organic matter. This side contains a model of a soil fragment, with dry leaves, fungi, and millipedes that can be touched.

Continue to the last room. Here, you can observe the winter in the Nature Reserve.

The central block of this last room tells what the mountains are made of, with photographs and information about the different minerals and rocks in the park: Quartz, granite, and gneiss, with an example of each material that you can touch.

These rocks have various applications in construction, decoration, and industry. Granite, for example, is commonly used for countertops and monuments because of its durability and aesthetic appeal. Quartz is used to manufacture glass and electronics, while gneiss can be found in building construction and as a paving material.

You will also find information on the winter dormancy of wildlife and the migration of birds to these forests.

The third side of the block presents the evolution of the Nature Reserve since the Palaeozoic era, over 250 million years ago. Small blocks contain information about the main trees in the park: chestnut, holm oak, Pyrenean oak, and chestnut.

You can see a life-size model of a black vulture hanging from the ceiling. Interestingly, black vultures seem to be pickier than griffon vultures when eating carrion. They act quickly when approaching a corpse, competing to get there before others. They prefer to tear the skin and focus mainly on consuming muscle tissue, avoiding the entrails. They then complete their diet by catching small animals such as squirrels, lizards, and turtles, which they carry back to their nests.

From the windows surrounding this space, you can see the grounds of the park house and the buildings that make up the old resin factory.

Between the winter and autumn halls, you will find the terrace, from where you can take in the reservoir, see the outbuildings of the house. and the hermitage of Carmen in the background.

The hermitage is closed all year round, except for the mass commemorating the saint’s feast day. In 1936, resin and wood began to be exploited in the forest and since then the festivities of Our Lady of El Carmen have been celebrated. Although nowadays these jobs have disappeared, this festival is still going on.

Exit the exhibition hall and head to the right, walking along the path to the entrance. On the right, you will find the Arboretum and signs with information about it. Each tree has a sign with its name on it and information about the chestnut groves is available on posters.

Chestnut trees are up to 30 metres tall, with straight, short, thick trunks and smooth, ash and brown bark when young, then dark brown.

Walk to the Memory Corner building, dedicated to the communities that contributed to the Iruelas Valley being the way it is today. Entrance to the building is not allowed, so the visit is limited to looking through the windows.

Next to this house is the only preserved saw of the old sawmill. In the window in front of the sawmill, the materials and tools used in the sawmill are displayed. A sign in ink and Braille tells you about the resin and wood industry.

Another window shows the resin work.

The following window shows what life was like in the village. It contains pottery used daily by the people of the village, metal jars of different sizes, and a desk with books.

The fourth and last window informs you about the forest rangers and their importance in the conservation and management of the valley. There are tools of the environmental rangers.

In front of the house, there is a life-size sculpture of a resin worker working the resin on a log.

The work of the resin workers focuses on the extraction of resin from pine trees. It starts with the preparation of the tree, where an incision is made to reach the wood containing the resin. The resin flows towards the incision and is collected in pots. The resin harvesters collect the resin on a regular basis, and their work contributes to the sustainable care of the forests. Their work combines traditional knowledge with modern technologies, forming a connection between forest management and the chemical industry.

Follow the tour of the site. You will now reach a panel showing the butterfly oasis, here you will find some of the plants on which these insects feed.

On the way to the reception house, you will also find a bird observatory, in front of which is the building that houses the audio-visual room, which is also used as a temporary exhibition hall and a multifunctional room for conferences and workshops.

An access ramp leads to a carousel and a children's area.

A gate grants access to the accessible path, which is considered a route annex to the house.

With this audio track, the visit to the Iruelas Valley "Las Cruceras" Nature Reserve Park House comes to an end, where you have bit a little more about life in this area. If you would like more details, you are welcome to come to the reception desk or ask any of the workers at the Park House.

Thank you for your visit.