Allée couverte, située sur l'estran de l'île Coalen
MonumentHidden Treasure
Allée couverte, située sur l'estran de l'île Coalen, located in Lanmodez (Département 22), is a historic monument. The monument is currently closed to visitors.
Key facts
- Type
- autre
- Location
- Lanmodez, Département 22, Bretagne
- Visit
- Closed to visitors
- GPS
- 48.8474, -3.0815
- Mérimée Reference
- PA00089257
Surgissant de l'estran à marée basse, l'allée couverte de l'île Coalen défie le temps depuis plus de 5 000 ans. Ce dolmen marin, entre ciel et mer bretonne, offre une communion rare avec le Néolithique armoricain.
History
Off the coast of Lanmodez, in the rough waters of the Goëlo coast, Coalen Island is home to one of the most unusual megalithic monuments in the Côtes-d'Armor region. The covered walkway here is only accessible at low tide, making the visit an absolute exception: travellers have to deal with the cycles of the ocean to get close to these thousand-year-old stones, as if the sea itself were their guardian. The covered alleyway on Coalen Island belongs to the large family of Neolithic collective burials that punctuate Brittany with their mineral silhouettes. Built along an elongated axis, it is made up of large granite slabs laid vertically in a row, covered by massive roofing slabs forming a funerary corridor. This type of megalithic architecture bears witness to an organised Neolithic society, capable of mobilising a considerable workforce to honour its dead and structure its symbolic territory. What makes this monument truly exceptional is its geographical location: resting on the foreshore of an island, the covered walkway has been partially washed away since it was built over five millennia ago. In Neolithic times, sea levels were significantly lower, and what is now an island was probably a peninsula or coastal promontory that was easily accessible. Over the centuries, the sea has redesigned the landscape around these unchanging stones. The visit requires careful preparation: check the tide tables, put on sturdy boots and be prepared to walk on the sometimes slippery foreshore. As a reward, the silence of the island, the cry of the gulls and the low-angled light of the Armor wrap the monument in a timeless atmosphere. Photography enthusiasts will find some striking shots here, where the Breton granite converses with the reflections of the Atlantic. Classified as a Historic Monument since 1975, this site is one of the most moving testimonies to the presence of prehistoric man on the Breton coast, where the earth ends and the vastness of the ocean begins.
Architecture
The covered alleyway on Coalen Island displays the architectural features typical of megalithic burials from the Armorican Neolithic period. It consists of an elongated burial chamber delimited by orthostats - slabs of granite set vertically on either side of a longitudinal axis - on which rest large horizontal covering tables forming a continuous stone roof. This arrangement creates a relatively narrow interior corridor, accessible via an entrance slab at one end. The total length of the building is typically between eight and fifteen metres for this type of monument, with an interior width of around one to one-and-a-half metres, and a ceiling height of one to one-and-a-half metres. The materials used were exclusively local granite, a rock that is abundant on the Armorican coast and particularly resistant to marine and atmospheric erosion. Neolithic builders selected naturally flat blocks or roughened them by percussion to obtain satisfactory contact surfaces. The blocks were assembled without mortar or binder, relying solely on gravity and the balance of their masses - a technique known as cyclopean construction - whose durability, proven over more than five thousand years, bears witness to the remarkable technical mastery of the prehistoric builders. Its location on the island's foreshore gives this monument a notable structural feature: the foundations are subject to permanent humidity and the effects of salt spray, which may have partially altered the stability of certain orthostats over the millennia. The orientation of the alleyway, probably set on a significant astronomical axis like many monuments of the same family in Brittany, warrants in-depth archaeoastronomical study to clarify its original cosmological logic.
Related Figures
Communautés néolithiques du Trégor (bâtisseurs, vers 3500-2500 av. J.-C.)Prosper Mérimée (inspecteur général des Monuments Historiques, pionnier de l'inventaire du patrimoine mégalithique breton au XIXe siècle)James Miln (archéologue écossais, explorateur précoce des mégalithes armoricains au XIXe siècle)René Galles (archéologue breton, fouilles de monuments mégalithiques des Côtes-du-Nord au XIXe siècle)Paul Du Chatellier (archéologue finistérien, systématisateur de la classification des allées couvertes armoricaines)
Tags
Nearby castles
Frequently Asked Questions
Where is Allée couverte, située sur l'estran de l'île Coalen located?
Allée couverte, située sur l'estran de l'île Coalen is located in Lanmodez, Département 22 department, Bretagne region, France.
Is Allée couverte, située sur l'estran de l'île Coalen open to visitors?
Allée couverte, située sur l'estran de l'île Coalen is currently closed to visitors.
