Welcome to Las Loras Geological Reserve,
a UNESCO Global Geopark (UGG) since 2017

Las Loras UGG comprises different spaces with common geographical, morphological, cultural, historical and economic features. All of them united by a common geological history, which constitutes the distinguishing mark of the territory. The landscape shapes are the first to catch our attention. The “tables” or Loras, which seem like natural castles, on which populations have settled down since the Neolithic, have been shaped by the wind, and mainly by the water, both on the surface and deep underground, causing formations like Las Tuerces, and caves and upwellings like the Cueva de los Franceses Cave and Covalagua valley. Several surprises and contrasts are also provided by the moorland, due to the incisions of the rivers.

The oldest rocks are 215 million years old and we can travel in time from the past to the present throughout the different trails, discovering and understanding how these rocks were formed. We will see how a continental fluvial area was invaded by the sea, which left its traces in shape of sediments that were transformed into the rocks which we now see and step on. Fossils will help us to understand the climate and the landscape at every moment. We will also observe how the rocks were folded and fractured by the several strains they were submitted to, and that finally eroded them in an original way, making the synclines one of the most exceptional elements of this landscape. We will learn much more along our trail as we will be able to observe great diversity of plant and animal species, due to landscape variety. We will see how these features predetermine human activity, settlements, architecture and local economy, on balance their inhabitants’ way of living. 

Geographical framework

The Geopark is located to the north of Castile and León, halfway between Palencia and Burgos provinces as a link between the mountain and the Castilian tertiary basin. The mountain ridges are oriented from east to west, with an altitude between 1,000 and 1,377 meters (Peña Amaya). The lower territories comprise a smaller area and are at an altitude of about 900 meters.

The water network of almost all of the Geopark is framed within The Duero Basin, being the Pisuerga River and its tributaries (Camesa, Lucio, Monegro and Sauquillo) the most important ones. The northeastern and eastern areas of the Geopark are bounded by the Ebro and Rudrón rivers. All of them are deeply incised in the reliefs, cutting the geological structures. 

Regional geological framework

The Geopark is geologically framed to the south and southeast of the Asturian Paleozoic Massif, which is here divided into Cantabrian Area, Fold and Nappe Province and Pisuerga-Carrión Province.

Part of two of the several units established for Mesozoic materials of the Basque-Cantabrian Region can be found inside the Geopark. On the one side, the Burgos Platform (Cantabria-Navarra Domain) that comprises the northern area of the Geopark, and on the other side, to the south, the so called Folded Band (Periasturian Domain). They are both divided by the Ubierna Accident, an important system of geological fracturing. 

Material dated between the Upper Triassic (ca. 215 Ma) and the Upper Cretaceous (ca. 66 Ma) – there is an almost complete registration between both ages – emerge in the whole territory of the Geopark, besides Quaternary material. The fossil sites are very significant: Jurassic fossil site in Rebolledo de la Torre and also in Camesa train station (Aguilar de Campoo), the fossil area in the lignite mining site (Cenomanian) in Rebolledo de la Torre and all the fossil area in La Rad and Barrio Panizares (Upper Cenomanian – Lower Santonian).

Inverted reliefs, mainly at the syncline structures (El Bernorio, Las Tuerces, Peña Mesa, etc.)

Crests are protuberances produced by a stronger layer. This is how cornices are formed (the edges of moorland), bars (as the one formed at the northern side of Peña Mesa syncline), fold-thrust structures (on the Jurassic material at Villela Fault).

Structural Planes, within the whole Burgos Platform and the “tables”.

Karst landscape formed by the action of surface and deep underground water. The several evolution states of a karst massif can be observed within the Geopark. On the surface we can watch dolines, karren, sinkholes, canyons and passages. In the deep underground there are galleries and caves. Many of these elements can be watched in Valdivia moorland and in Las Tuerces we can watch not only these elements but also other forms which were capriciously shaped by the water. 

Flora

In Las Loras upper part vegetation consists of herbaceous plants and small bushes. The presence of hazelnut trees at the several dolines extended along the carbonate moorlands is a curious fact. At lower sites great anthropization has occurred due to farming practices.

The presence of calcareous material (limestone and marl) and detritus material (sandstone and conglomerate) often determines the type of vegetation. The colonization of heather and broom in acidic terrain where sandstone and conglomerate are predominant is a clear example of this. 

The presence of Holm oaks, oaks and beech is usually determined by the orientation of the slope. Holm oak and Lusitanian oak develop on the southern side, while oak and beech develop on the northern one.  

Riverside woods flank the rivers. You can also see pine forests due to afforestation.

Fauna

There are several fauna species. Those connected to Holm oak woods: wild boar, roe deer, deer, wild cat, weasel, and dormouse; goshawk, sparrowhawk, booted eagle (an endangered species), short-toed eagle, tawny owl, European green woodpecker, great spotted woodpecker, Eurasian nuthatch, Eurasian hoopoe, chaffinch, European crested tit, common wood pigeon, cuckoo and coal tit; Montpellier snake and ocellated lizard. In the moorland we can watch: Eurasian skylark and Dupont’s lark, Thekla’s lark and tawny pipit and reptiles such as vispera latastei, lizard, podarcishispanicus and muralis. Calcareous collapses are ideal for the breeding of crag martin, wallcreepers, common rock thrush and blue rock thrush and chough. It is also possible to watch peregrine falcon and Egyptian vulture.

The presence of the wolf (protected species) has been confirmed for long with structures like Valcabado wolf lair. 

In the areas growing cereal it is easy to watch both hen and Montagus’ harrier and other birds of prey such as common kestrel, kite, buzzard and merlin. Among their prey we can find saxicola, wheatear, corn bunting, partridge, quail and many alaudidae. There are migratory species, in summer we can watch the hobby and in winter vanellus. And of course there are also corvidae (raven, rook, western jackdaw, carrion crow, magpie), which are represented in high and expanding number. 

In the territory we can also find some mammals like hares, rabbits and voles. The fauna in oak woods is similar to that of Holm oak woods, where northern species like the squirrel, shrew, woodcock, salamander and common frogs can be watched. 

Human activity

In spite of the biodiversity assortment, we can say that the landscape has been quite hostile what concerns human settlement. There are Neolithic remains, Pre-Roman forts and more recent archaeological remains, as some places were used because of their strategic features during Civil War, for example. 

The extraordinary morphology, the moorland extreme conditions and the incision of some of the rivers have made it difficult for humans to settle and the small villages are scattered along narrow valleys, where communication is quite complicated, what has always meant a certain degree of isolation throughout history. Nevertheless we must highlight the beauty of the villages and the architectural surprises which can be found in them. They are built in limestone and sandstone, which make us think of geology as the link of all these places. On the other hand, the use of land meant a lot of creativity which transformed the land into pastures and crop areas, mainly in the narrow valleys of the rivers, where the incision itself created a microclimate favouring the growth of some products like potato. Also in the calcareous moorland, in the deep dolines and uvalas originated by the erosion of water, very fertile red clay was accumulated, enabling cultivation throughout time.