The shape of the grove is that of a stronghold, probably Carolingian, at Colline-Beaumont which overlooks Eu (Seine-Maritime) and the sea.
Plant transformations of the past are everywhere around us, especially in hedged farmland.
If a grove has a strange shape, it means it has a strange history… The same is true for unusual arrangements of lines of trees and hedges.
At Lawarde-Mauger (Somme), the trees delineate an earth levee that protected the entrance to an underground shelter where the peasants would hide with their goods and animals during the wars of the sixteenth and seventeenth centuries.
The photographs of Folleville (Somme) clearly shows how the moats that surrounded a feudal ruin were taken over by trees. When the tower collapsed, only the circle of vegetation remained.
The oppidum at Incheville (Seine-Maritime), ringed by its wooded slopes.
Sometimes it is only the land allotments that cause the location of a stronghold to appear in an unusual way, like at Ors (Pas-de-Calais). It is true that a long rainy period filled the ancient moats, which are generally invisible.
This star-shaped grove north of Amiens is where a small, early seventeenth-century bastion made of earth.
At Boismont (Somme), an ancient fortin is revealed by a circle of trees — as well as by its toponym, "le Fort".