Rowan is a duchy in the Nilfgaardian Empire presumably in the vicinity of Ymlac and quite far from the capital. At least one river flows through the duchy, in a hilly region forested with evergreen yews where Darn Rowan stands. Mandrake is cultivated on a small scale in the area.
The coat of arms for Rowan is not actually described in the novels. These particular coats of arms were designed by our resident heraldry and Witcher expert Mboro.