Minecraft wiki entry for Infdev_20100327_to_Beta_1.7.3, associated text: Sometimes, there are extremely tall pillars of gravel that stretch from the ground to the ceiling of a layer. Likewise, some of the beaches that collapse create pillars of sand all the way down to the ground, despite there not being that much sand, to begin with. The Corner Far Lands is also prone to having near-perfect diagonal lines being carved into the ceilings or floors of layers. If traced, these lines all intersect at the corner (X/Z ±12,550,821). This seems similar to how the Edge Far Lands have a consistent pattern along lines perpendicular to their edge, but is much less pronounced.