I've been working to try and fix this by making a new world several times to no avail. I even made a single player world and just dragged it into my craftbukkit server, and had this happen. The chunks/biomes load randomly like this, and at different elevations usually causing large flat walls or canyons. Does anyone know why this is happening or how I can fix it? EDIT by Moderator: merged posts, please use the edit button instead of double posting.