アルモリカ山塊
The city was born under the name of "Briovera" on a rocky outcrop of schist belonging to the Armorican Massif, in the Cotentin Peninsula, between the confluences of the Vire – which dominates the city centre – with the Dollée and Torteron, two rivers channelled in their urban sections. This historic heart of the city became "L'Enclos", a site well suited to passive defence.