Minecraft wiki entry for Advancement_guide, associated text: The simplest and intended method of attaining this advancement requires finding iron ore (though iron ingots can also be found elsewhere, such as village blacksmiths and dungeon chests). It's easiest to find iron ore in caves, but because caves have monsters in them, they are not recommended to adventure into them until you have some armor and weapons. If you're lucky, you will find an exposed surface with iron ore. Otherwise, you can start a mineshaft. If you are feeling very daring and adventurous, make a stone sword and a few torches, and go ahead and search a cave. Torches can be made once you find coal, which is very common. You can usually find iron in caves very quickly, unless they are high in the air.