The Slack River estuary and dunes form a vibrant ecosystem that spans more than 200 hectares. This site is the result of the interaction between the sea and the shore, providing a diverse habitat for many animal and plant species.
Ambleteuse
The site is accessible all year round
Free
Picnic area
Facilities
Accessible by public transport
Dogs welcome
Viewpoint
Toilets
Car parking
Disabled parking
Geosite details
The Slack River estuary and dunes form a vibrant ecosystem that spans more than 200 hectares. This site is the result of the interaction between the sea and the shore, providing a diverse habitat for many animal and plant species. The dunes, with their shifting shapes, are constantly changing and provide a refuge for specific flora, such as halophilic plants, adapted to the salinity of the environment.
Nearby, the Fort d’Ambleteuse, built in the 18th century, adds a historical dimension to the landscape. Its construction used local stones, strengthening the link between the built heritage and the geological resources of the region.
The Slack River estuary is also a prime location for birdwatching, especially during migration periods. Nature lovers will be able to spot herons, ducks and other aquatic species that frequent the area. This site is ideal for family walks, with rest areas and sea views, allowing you to fully enjoy this rich and varied natural area.
The 'Big Bang'
13.8 billion years ago
Earth formed
4.6 billion years ago
540 million years ago
The Cambrian explosion of life: animals evolved and diversified as never before on Earth.
Devonian
419 million years ago
390 million years ago the oldest rocks you can see in the Geopark date back to the Middle Devonian. They are still quarried today in the Marquise basin in France.
Carboniferous
359 million years ago
Around 325 million years ago the Geopark was near the equator. The swamp forests from that period are preserved as coal, which was formerly mined in the Marquise basin in France as well as in East Kent and the Nord-Pas-de-Calais.
Permian
299 million years ago
Triassic
252 million years ago
210 million years ago the Geopark was in the centre of the Pangaea supercontinent, and dinosaurs roamed the land!
Jurassic
201 million years ago
150 million years ago the Geopark was submerged under the sea, the sands, clays, limestones, and sandstones that compose the Boulonnais region in France were deposited.
Cretaceous
145 million years ago
Over about 40 million years from 100-60 million years ago, Chalk formed at the bottom of a warm, shallow sea where the Geopark is located today. This was the first step towards the formation of our distinctive chalk landscape, which defines much of the Geopark.
Palaeogene
66 million years ago
Tectonic activity around 40 million years ago uplifted the territory of the Geopark by dozens of metres, creating an extensive chalk landscape that connected France and Great Britain.
Neogene
23 million years ago
Quaternary
2.6 million years ago
450,000 years ago, a megaflood destroyed the chalk ridge connecting Calais and Dover, creating the iconic white cliffs of the Geopark we see today
