The crater of Osrakum containing the Skymere and, in the midst of this lake, the Isle. Here is the much smaller cone and crater which the Masters call the Plain of Thrones, the Labyrinth, the Pillar of Heaven and the Forbidden Garden of the Yden.
The edge of the large almost submerged crater is the Ydenrim and holds within its circle the Yden and the Pillar of Heaven. The ‘orange crescent’ within the Ydenrim is the region that is filled with shallow lagoons.
The Sacred Wall of the crater is cut along its inner edge by the coombs of the Chosen and is only fully breached by the Canyon of the Three Gates which leads out to the City at the Gates.
I made this model as a way of trying to fully understand the complex landform which I had produced with the help of Ben Harte.