After the Congress of Vienna in 1815, the Swiss part of the ancient Baronie formed the community of Goumois in Switzerland (Canton Jura), the French part formed the community of Goumois, Doubs in France (Département du Doubs)
The landscape is characterised by granite rocks and harsh mountains that, even if not particularly high, have constituted for millennia a barrier between this region and the nearby territories of Baronie and Montalbo.
Some few miles from hence upon the same river standeth Trematon, bearing the name of a Castle, though the wall be halfe downe, in which, as we find in Domesday booke, William Earle of Moriton had his Castle and held his mercate, and was the capitall seat of the Baronie belonging to the Earles and Dukes of Cornwall, as we may see in the Inquisitions.