Minecraft wiki entry for Nether_hub, associated text: Now you will be making the map. You will want blocks such as green and blue wool/concrete/concrete powder for the land and water, then possibly sand or even gravel for deserts and gravelly mountains. Note that if you are using concrete, you will have to harden it in the overworld before you place it (just a friendly reminder so you don't have your day ruined by realizing that your brilliant plan is not so brilliant.) Hold a map of the area you are working on in your off-hand so you can reference it easily. Remember that each block you place in the nether represents an 8x8 area in the overworld.