Luckily installing custom maps for Minecraft has only gotten easier over time thanks to the dedicated Minecraft Launcher for the Java edition of the game. Navigate to the "Installations" tab and hover over any of the available game builds. Click the folder icon to open your Minecraft game directory and find the "saves" folder.
You should have downloaded a .zip folder for the map you're planning to play. Unzip that folder and add it to your Minecraft "saves" folder. You should now see the custom map in your singleplayer world options when you launch the game.
Pay attention to which version of Minecraft each map is meant to be used on as some may not function properly on newer or older versions of the game than they were built in. We've listed recommended versions for each of the custom maps in our list below.
Witchcraft and Wizardry is a whole Hogwarts-themed RPG inside Minecraft complete with quests, minigames, and some familiar faces all inside an enormous and intricate recreation of the boarding school castle. We played through a bit of it and found it to be a fun, nostalgic adventure. You start off your Hogwarts adventure by buying school supplies at Diagon Alley and then rushing off to get sorted into a house before you begin attending classes. It works in multiplayer too, in case you'd like to co-op it with friends.