Natural environment

Discover all the protected natural spaces that we will cross during the route, one after the other

Natural environment

This mountain route crosses a large number of places of natural interest, protected by their high environmental value, the diversity of fauna that they host, and the high landscape interest that has made it one of the most visited areas of the Eastern Pyrenees. Let’s get to know these places in a bit more depth.

Areas of high natural interest

Mountain sector of the Carlit massif – Campcardós

Located at the confluence of Mediterranean, Atlantic and mountainous climatic influences, it offers the possibility of discovering more than a thousand plant and animal species. This massif, crossed by the Querol valleys to the west and surrounded by the Alto Valle del Auda to the east, concentrates the highest peaks of the Catalan Pyrenees (Carlit – 2921 m, Puig Pedrós – 2905 m). On the Carlit lake plains, the landscapes of the old glacial valleys are today covered with lakes, rock and plant species, forming landscapes of great interest to hikers and naturalists who visit them. This area is recognized as being of European interest within the framework of the Natura 2000 network, and has other environmental recognitions at the French state level.

Classified Natural Area of La Bullosa

The Lago de la Bullosa is an artificial lake in the highest part of the Tet river basin, 2,016 meters above sea level. Its Catalan name “La Bullosa” derives from the adjective “bullosa” that is, it makes bubbles.

If we do a bit of history, the dam itself was built between 1903 and 1910. Its mission was to regulate the flow of the Tet River, and to provide electricity to the Yellow Train through several hydroelectric power plants distributed along the course from Tet. Since 2008, after major works, part of the volume of water has been used to feed the snow cannons produced at the Font-Romeu and Pyrénées 2000 ski resorts. . The lake has a capacity of 19 million m³, and it is full in summer and almost empty in winter.

Pantano de La Bullosa, Source: A Pas d’Isard

The great lake and its surroundings are a classified natural site since June 24, 1976, by virtue of the law of May 2, 1930. With the aim of preserving this natural heritage, the Council of the Eastern Pyrenees begins to regulate tourist traffic since 2000, limiting its access by road during the months of July and August, and making it only accessible with a bus, the Font-Romeu chairlifts and trails marked by access on foot.

It is the highest lake that can be reached by road or by chairlift along the Pyrenean massif. The large areas of pasture also delight visitors, who stroll amid the large herds of cows and horses that graze throughout the summer. The ancestral grazing rights, and some parcels owned by the enclave of Livia, cause herds to mix from both sides of the border, an unusual fact in an area already relatively far from the artificial limit raised by the Treaty of the Pyrenees.

Lakes of the Carlit

The landscape between Bollosa and Carlit, sometimes described as lunar due to its large rocks, and the multitude of small lakes along the way to this summit, are the main charms of the place. The place has also been called the Carlit desert, a name that is shocking for a plain that contains so much water; but that in winter, yes, it is a true white desert. In places with little passage, marmots are installed in their burrows, and chamois graze the fresh grass watered by the ponds.

Lakes below Pic Carlit, Source: A Pas d’Isard

Classified site of the Camporells Lake Circus

Easily accessible, this area rich in remarkable flora and fauna, appreciated by hikers and fishermen, is also a space for grazing and forestry activity. An exceptional landscape that combines crystalline mountain lakes with high peaks such as the Perics, large rock slopes, and wooded slopes until they touch the waters of the ponds. In winter the place is a must for mountain skiers.

The quaternary glaciers have carved cirques and basins, and successive lakes have formed on the rocks that give landscapes comparable to those of the Aigüestortes i Estany de Sant Maurici National Park. . Climate and vegetation make a reserved paradise, full of softness, a luminous territory where the blue of the lakes can be seen through the branches of the pines.

Lanós Lake

Among the great Pyrenean lakes, situated at an altitude of 2,175 meters, Lake Lanós is usually a meeting place for lovers of fishing. It offers a good view over Carlit, Puig Pedrós de Lanós, and Puig de Coma d’Or. A true inland sea 3 km long and 800 m wide, the Lanós is an immense reservoir of water, a large lake in which the initial depth of 55 m was raised to 85 m by a dam. This lake was already the largest in the Pyrenees before the works, and with them it has been reaffirmed. The paths around its surroundings offer good observation points to see the wild mouflon that, although they are called Pyrenean mouflon, have repopulated here brought from Corsica. In its surroundings we find ponds such as Font-Viva, Rouzet, Lanoset, or Vésines ponds going down the Coma d’Anyell valley.


Muflones, Source: Corriols de Llum

Classified natural spaces

Regional Natural Park of the Catalan Pyrenees:

The great natural park of Northern Catalonia, covers 138,000 hectares between the regions of Alta Cerdanya, Capcir and Alto Conflent, in the French department of the Eastern Pyrenees. It houses 64 municipalities, some 21,000 inhabitants, and seven nature reserves. Crossed by the yellow train, which runs from 1910 to 62 km between Vilafranca de Conflent and La Tour de Carol, the park also has nine ski resorts and three thermal water baths. With an altitude gradient between 300 and 2,921 m, this territory was recognized in 2004 as the 43rd Regional Park in France thanks to the richness and fragility of the heritage it contains. Under the gaze of the bearded vulture and the chamois, the Catalan Pyrenees is rich in both Mediterranean and mountainous influences, influences that confer an almost unique ecological diversity, housing more than 240 protected species, of which 49 are endemic. This natural wealth also translates into the use of resources in all forms of green energy: generation of hydroelectric energy in large dams, generation of solar energy in the Odeillo solar furnace, high use of wood as fuel, and use of of geothermal energy in many places that enjoy natural hot water elevators.

What is a Regional Natural Park?

The Decree of September 1, 1994 defines the raison d’être of a regional park as “a territory of fragile balance, and threatened with a rich natural and cultural heritage, which is the object of a territorial development project based on conservation and valuation of this heritage “. The creation of regional natural parks is the responsibility of the Regions and their creation is based on a voluntary approach expressed by the municipalities and led by the Region, with the classification that the State assigns to its national brands. A territory is classified as a Regional Natural Park by decree, and it is assigned the Regional Park brand of the Ministry of the Environment, a brand designed to promote a quality image, linked to the heritage protection and development activities carried out in the territory. The classification of a regional park is reviewed every ten years.

Orlu National Wildlife Reserve

Founded in 1943, the Orlu reserve, of 4,250 ha, became a national wildlife reserve in 1998 due to its high heritage value. The National Office for Hunting and Wildlife ensures regular monitoring of the biodiversity of many mountain species, such as the chamois that runs at home on the steep slopes of the nature reserve, the marmots that whistle among the little pancakes on the way. of hikers, or large vultures and kestrels in the sky. A morning walk will allow us to get to know the reserve well and see, most likely, many of these animal species.

Common trout

The most emblematic species of the Pyrenean rivers and lakes

The common trout (Salmo trutta) is a species of fish typical of fast-flowing cold-water rivers. It is found naturally in the main rivers of these characteristics in the Nearctic region in practically all of Europe. . In the Catalan Countries it can be found in the rivers of the Ter, Llobregat, Ebro / Segre, Júcar, Turia and Garona basins. It normally occupies well oxygenated and cold rivers, occasionally it can also be found in lakes.


The adults of this species measure between 33 and 41 cm in length, although some exceptional individuals can acquire greater dimensions (some individuals of more than 13 kg and 90 cm in length have been documented). The color is a golden brown with spots along the entire back from head to tail.

: Rainbow Trout, Source: Viquipèdia


Despite the relative stability of their population sizes, one of the biggest problems that arise is the fragmentation of their populations due to the presence of reservoirs, especially in the courses of the Ebro / Segre basin and the introduction of specimens from Central Europe, today practically non-existent, but carried out with some frequency between the s. XIX and well into the s. XX. These introductions of non-native specimens produce a loss of the rich genetic diversity present in the Iberian basins. It has been verified that there has been hybridization between the allochthonous and autochthonous individuals.


Young trout feed mainly on insects. Adult trout actively hunt for prey, and their diet consists mainly (80%) of other smaller trout. The rest consist of tricopters, snails, crustaceans, and amphibians.

From the 3rd or 4th year of life, trout reproduce every year and are not monogamous, that is, they do not keep their partners. The setting occurs between October and December and fertilization is external: the males make a furrow in the river bed that they defend from other males, and eventually they appropriate other furrows made by less aggressive males. The female chooses one of these beds for laying. The male then fertilizes this clutch. At this time the laying is abandoned by the parents who do not perform any other care.

If you want to know more details about trout, you can watch this video, from the Beasts program on TV3, which delves into the ecology of this species and the high mountain lake ecosystems, focused in this case on Pallars lakes, with characteristics practically identical to those of the Capcir and Cerdanya lakes.

The lakes of the Carlit 50 Estanys route are subject to various regulations regarding fishing and bathing, so it will be good to ask for advice before practicing any of these activities.

Some geography: the three regions that host the route

The Capcir

Its nickname is Little Canada for its vast wild spaces, and it is the highest inhabited plateau in Europe with an average altitude of 1.500 m. . The quaternary glaciers, a geographical period of 2.6 million years to date, have shaped fascinating landscapes such as the Camporells cirque, the eroded Madres relief, or the Galba glacial valley with the characteristic U-shape. A natural environment of high ecological level that presents protected species such as the white partridge, a bird that changes color according to the season to adapt to its natural environment, the high mountains, or large forests such as the forest of La Mata, with the extravagant shapes of hooked pines , which offers numerous family activities both land and water; and agriculture is still alive, which has also changed the landscape throughout its millennial use.

Lake Matamala, El Capcir, Source: A Pas d’Isard

La Cerdanya

This cross-border plateau at 1,200 m altitude, the most extensive plain above 1,000 meters in Europe, is ideal for research and improvement of the physical performance of high-level athletes, with the Font- Romeu. La Cerdanya enjoys both flat and mountainous territory, very sunny, with more than 3,000 hours of sunshine per year, so it is not surprising to find research centers on solar energy such as the Thémis power plant and the solar ovens of Odeillo and Mont – Luis (the oldest solar oven in the world). Another of the peculiarities of the territory is the enclave of Llívia, the result of history with the past struggles between the kingdoms of France and Spain, which ended in 1659 with the Treaty of the Pyrenees. All of the Catalan land, fits in with the Alto Ariège (Occitania) in the area of the Puymorens pass and the Lanós lake.

The Upper Ariège

This region, fully on the northern slopes of the Pyrenees, is the most mountainous part of the Occitan department of Ariège, in the Midi-Pyrenees region, and takes its name from the river that rises under Pas de la Casa (Andorra) and is It extends from the Coll de Puymorens to the Garonne.

The valleys of Ariège are choppy, very long, wild and with a unique character. At the bottom of the valleys, living conditions have been very harsh, its towns are small, poor, with an aging population, although it is a frontier land, and for a time they were the promise land of many Republican Catalans and Spanish.

Some important prehistoric caves stand out, and recently the spread of Catharism has given it a certain media presence.