©M. Rivrin
The Guillotin oak A thousand-year-old tree

The Guillotin Oak

On the edge of the road leading to Tréhorenteuc, stands one of the most remarkable trees of the forest of Broceliande. Standing at the exit of Concoret, it is the guardian of the passing time and the memory of men, the majestic ancestor, imperturbable witness of the small and great events of the magical forest.


Its circumference of about ten meters and its venerable age impose it as the natural master of its place. Here is the patriarch of the trees of Broceliande. No one knows the true of age of the oak, however traditionally we say its enchanted branches have stood for 1000 years. 10 centuries of stories and countless people and events. Some have definitely marked the tree. Or would it be the tree that has marked those?
The Guillotin Oak was designated a remarkable tree in 2017.


Few large oaks remain in Broceliande. For three centuries at least, the Forges devoured them. But the rare survivors remind us of the splendor of the forest in the successive times of the druids, the monks and the knights. The oldest of them all had the good idea of being easily accessible. At the edge of a road, the Guillotin oak shows its gnarled and tortured trunk. Its branches could be trees themselves, and in the thick wrinkled skin of its bark, a cave opens, dark and secret. The ancestor of the trees of Broceliande is hollow! Not so long ago, children would enter the blackened trunk by the dozen. Today, it is better to avoid this game, as it is painful for such an ancient being.

Text written by Claudine GLOT, Centre de l’imaginaire Arthurien .



Tourist Office of Ploërmel Community – site of Tréhorenteuc
1, place Abbé Gillard – 56430 TREHORENTEUC
Phone : 02 97 22 36 43
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Legendary sites Discover the other highlights of the forest