The Goelo is a coastal region of the Atlantic sea delimited by three rivers roughly forming a rectangular shape, with a length of 40 kilometers that extend 10 kilometers inland, for a total area of 530 square kilometers.
The southeast of the region is more elevated, with some hills reaching 250 meters, due to the presence of the Quintin massif where the sources of the three rivers are located.
The region can also be defined by the administrative limits of 38 communes: Binic, Cohiniac, Étables-sur-Mer, Île-de-Bréhat, Kerfot, La Méaugon, Lanleff, Lanloup, Lannebert, Lantic, Lanvollon, Le Fœil, Paimpol, Plaine-Haute, Pléguien, Pléhédel, Plélo, Plérin, Plerneuf, Ploubazlanec, Plouézec, Plouha, Plourhan, Plourivo, Plouvara, Pludual, Pordic, Quintin, Saint-Donan, Saint-Quay-Portrieux, Trégomeur, Tréguidel, Tréméloir, Tréméven, Trémuson, Tressignaux, Tréveneuc, Yvias.
The Goelo has 82 582 inhabitants (INSEE 2013), and a population density of 156 per square kilometers.
According to CORINE Land Cover inventory (CLC 2012), most of the land is used by agriculture (76 %), with the rest divided between artificial (13 %) and forest or semi natural areas (11 %).