El Yermo was a tardic name given to the lands east to the Osorio river -known as well as the Barlans-, which means the Wilderness. It received this name as these lands were scarcely inhabited, mostly only by barbarian kanovs.
Quite frequently, 'El Yermo' is used almost as another word for 'the Barlans', excluding only the peninsula of Gorbegea, which is sometimes considered part of the Barlans. Sometimes it's exclusively used to refer to the western Barlans, between Lake Andas and the Osorio River.