The Toina valley is a region in the Narok. Cities in the region, like Aedd Gynvael which is located in the valley, are governed by officials in Rakverelin. The river Toina runs through the valley as well.
This area is incorrectly sited on almost each published map pertaining to the Witcher series. Maps usually show it as being in the north or northeast of Kaedwen when it is in fact in the western region of the continent.