Hydrography

Durantón River

The Duratón River flows through the provinces of Madrid, Segovia and Valladolid.

The river has a length of 106 km and rises in the municipality of Somosierra, Madrid, in the area where the streams of La Pedriza and La Peña meet. The river flows into the Duero River at the town of Peñafiel in the province of Valladolid.

The River de la Hoz or River Ayuso, the River Serrano, the River Caslilla and the River San Juan or River Prádena are all tributaries of the River Duratón, which flows through the municipality of Duratón in the province of Segovia.

One of the most impressive natural sites along the river is the Parque Natural de las Hoces del Río Duratón, which has been protected since 1989. The site is situated in the Sepúlveda massif, in the north-east of the province of Segovia, in the middle course of the river. The area extends to the Burgomillodo reservoir, covering more than 5,000 hectares.

The park follows the course of the river for 25 km and is characterised by deep rocky cliffs, which at some points reach a height of more than 100 metres.

One of the most notable features of this natural park is its significant population of griffon vultures (Gyps fulvus), which is one of the largest colonies on the European continent with over 575 mating pairs. Other notable avian species include the golden eagle (Aquila chrysaetos), the peregrine falcon (Falco peregrinus) and the Egyptian vulture (Neophron percnopterus). In recognition of its importance for birdlife, the park was designated a Special Protection Area for Birds (SPA) in 1991. It now attracts more than 130 species per year.

As for the predominant vegetation on the river plain, we can find typical riverside vegetation such as: willows (Salix), poplars (Populus) or alders (Alnus), with undergrowth populated by dogwood (Cornus), elder (Sambucus), blackberry (Rubus ulmifolius), wild rose (Rosa stellata), blackthorn (Prunus spinosa)and hawthorn (Crataegus).  In addition, rushes (Juncus), bulrushes (Typha latifolia), reeds (Phragmites australis) and cattails (Typha) can be found on the banks of the river.

In the higher areas further away from the riverbed, species such as Spanish juniper (Juniperus thurifera),, common juniper (Juniperus communis) or prickly juniper(Juniperus communis) predominate, as well as scrubland vegetation such as thyme (Thymus), aulaga (Genista scorpius), sage (Salvia officinalis) or lavender (Lavandula).

As for the fauna that populates the riverbed, there are abundant specimens of common barbel (Barbus barbus), carp (Cyprinus carpio), Duero bogue (Pseudochondrostoma duriense), common chub (Achondrostoma arcasii), goby (Gobio gobio) or common trout (Salmo trutta).

Mammals such as hare (Lepus europaeus), roe deer (Capreolus capreolus), wild boar (Sus scrofa), common fox (Vulpes vulpes), European badger (Meles meles), marten (Martes foina) and weasel (Mustela nivalis) roam the surrounding area.

In addition to birds of prey, you can also observe species such as the western jackdaw (Corvus monedula), red-billed chough (Pyrrhocorax pyrrhocorax), crag martin (Ptyonoprogne rupestri), rock thrush (Monticola solitarius), blue rock thrush (Monticola solitarius) or black redstart (Phoenicurus ochruros). As well as steppe birds such as the Dupont's lark (Chersophilus duponti), red-legged partridge (Alectoris rufa), Crested lark (Galerida cristata), Woodlark (Lullula arbórea) or Skylark (Alaudidae).