Next, a yellow octagon can be constructed such that its diagonal facets touch the corners of the orange box around the orange circle. Then, a yellow circle can be constructed around the octagon. The octagon will thus have facial diameter of 31.40m/cos22.5 = 33.99m, and the yellow circle will have diameter of 33.99m/cos22.5 = 36.79m. Note that the bottom point on the yellow circle locates the front edge of the squarish pool, and that the left point of the circle locates the middle of the wall between the two narrow halls. The top facet of the octagon, meanwhile, locates the wall to the left of the axial cryptoporticus.