| Municipalities | Miengo, Piélagos y Liencres |
| Protection figures | Declared Nature Park Dunes of Liencres and the Pas Estuary in 1986 |
| Other protection figures | Geological Importance Point and (SCI) Site of Community Importance in 2006 |
| Access | Regional road CA-231 which link Santander with Boo de Piélagos, once gone through the town of Liencres take the turning to the right (CA-305) which takes you to the Valdearenas beach, within the Nature Park. |
DESCRIPTION
It is the largest dune system in Cantabria, localized in the central area of the cantabrian coast, in particular, in the River Pas mouth. It is formed by the Pas Estuary and the Lincres Dunes.
The estuary, known as Abra de Pas, is situated between the municipalities of Miengo and Piélagos. It is muddy and contains a few small islets. Sandy areas are predominant where the Abra de Pas golf course is. There are intertidal areas, where the reeds are very common, in between the old watermills dykes.
The last section is fully dominated by sandy areas: The Liencres Dunes and Mogro (Usil) and Robayera (Miengo) beaches.
The first element on Nature Park´s relief is La Picota mount. By the Mogro beach there is a promenade.
FLORA AND FAUNA
The sandy areas have such weather conditions that allow for a type of flora that is characterized by plant with small and fleshy leaves to easily adapt to an environment with shallow salty waters. In additon, this environment is ideal to limit fauna presence.
The main faunal species are waders, inhabitant of muddy coastal environments. Waders have long beaks and legs that allow them to reach deep in the mud and feed of the invertebrates living there. Migratory and nesting birds are common on the park, as well as avocets and plovers.
ENVIRONMENTAL EDUCATION
To ease and protect the environment from visitors there are man built paths, within the park, with information and itenery boards. In addition, there is divulgative material where the main natural space features are described.
FACILITIES
The park is equipped with a large car park area, tables and benches for the visitors use and enjoyment. Free entrance.