Minecraft wiki entry for Mining, associated text: The more common version runs the ladders down the middle of the wide side, that is put blocks to break the fall on both sides every few levels, and at their mining levels, but another way to do it is to put ladders on one end, and put a waterfall on the other. They can then put a few blocks in the middle to prevent falls, but leave plenty of spaces to pop out of the waterfall for a breath.