Bundahishn
Chapter XI
On the day when Tîstar produced the rain, when its seas arose therefrom, the whole place, half taken up by water, was converted into seven portions; this portion, as much as one-half, is the middle, and six portions are around; those six portions are together as much as Khvanîras.
The name kêshvar ('zone or region') is also applied to them, and they existed side by side (kash kash); as on the east side of this portion (Khvanîras) is the Savah region, on the west is the Arzah region; the two portions on the south side are the Fradadafsh and Vîdadafsh regions, the two portions on the north side are the Vôrûbarst and Vôrûgarst regions, and that in the middle is Khvanîras.
And Khvanîras has the sea, for one part of the wide-formed ocean wound about around it; and from Vôrûbarst and Vôrûgarst a lofty mountain grew up; so that it is not possible for any one to go from region to region.
And of these seven regions every benefit was created most in Khvanîras, and the evil spirit also produced most for Khvanîras, on account of the superiority (sarîh) which he saw in it.