Minecraft wiki entry for Mining, associated text: Each connection is a hub formed by two of the cardinal branches intersecting, meaning if players went to the first north hub down, they would have to mine one push or hub to the left and connect to it from the first west hub down by pushing right. It's the same as the hub but it leaves two walls with nothing to do, if the player try to continue with them, they will get intersections that are hard to make aesthetic unless the player are looking for a large open mine, or a maze mine. Instead, the player can use it for chests, and it works well for its purpose. Very hard to describe with letters, so here's a picture instead: Picture