Sedimentary rocks cropping out the region constitute one of the most widely known field laboratories, visited by many geologists from all over the world.
On this singular substratum majestic landscapes develop, often populated by flora and fauna of a wide natural value.
Conca Dellà is surrounded by different mountain ranges that limit and define it as a specific area. Thus, on the west there is a single open 'border', the river Noguera Pallaresa. On the north, the Sant Corneli mountains and the vast Boumort mountain range, a famous Hunting Nature Reserve. On the east, the Benavent rock and the Comiols mountain pass, through which it was almost compulsory to pass in ancient times to enter the valley. On the south, the impressive Montsec mountain range, a true natural science school in Catalonia.
The whole area is a glare of singular vegetation and fauna. It is worth mentioning the large amount of vultures flying over the place, as well as the presence of the capercaillie at the Cimadal woods, where there is also a beech wood that is unusual in these lands.
One of the remarkable spots of natural interest within the area is:
The Basturs lakes, together The Basturs lakes, together with those of Banyoles and Montcortès, are the most important lakes of a karstic origin in Catalonia. In Basturs there are two lakes. The high amount of lime in its water conditions the existence of vegetal and animal species that cannot be found in other water spaces of the country. Due to its natural peculiarity, the lakes are included in the Natural Interest Spaces Plan of the Catalan Government.
The interior vegetation of the lakes is of an astonishing singularity. In the big lake, more than 120 different unicellular algae species have been found and, in the small lake, about 80. One of the unicellular algae found in the big lake is a species that does not live anywhere else in the world, the Ceratium cornatum. Outside the lake, in the brushwood area, there is a plant named Haplophyllum linifolium that cannot often be found in our country. The lake shore holds rushes, reeds and Claudium mariscus, a species which is not very common in Catalonia.
On the big lake surface, one may see a carnivorous plant, Utricularia vulgaris, which has no roots and lives floating on the water.