This board, by a large panorama, retraces Plancoët's history from Gallo-Roman times, and the Middle Ages with its walls and its castle.
François Renée de Chateaubriand, born in Saint-Malo, 25km away from Plancoët, often cam to visit his grand-mother: Madame de Bédée, "at the good air of Plancoët", where he frequented Clos Bourget, went on long walks by Brandefer Hillock and Nazareth, hamlet from Corseul, linked to Plancoët in 1841.
Plancoeët's economical development was linked to its port activity, the sea, that can be seen from the site, being only 4km axay, with the exploitation of marl, then dairies developed following alcohol distilleries, of which the old chimney can be made out, Sassay water plant coming in addition and to complete these activities.