All over Hogwarts’ outlying regions, The Highlands, you’ll often see a symbol that looks like an archway. These symbols signify dungeons. However, there are a select few of them: AKA 5, that are considered cairn dungeons.

For this trophy you need to discover, i.e. step foot into, all of the cairn dungeons dotted around the game world. You'll know what is and isn't a cairn dungeon by the outside of the dungeon itself. If there's a ton of rocks pilled up, like stonehenge, that's a cairn dungeon.

Check out all 5 Hogwarts Legacy cairn dungeon locations here.