In Baldur's Gate 3, players are able to explore a number of locations that aren't vital to progressing the story, an early example of this being the Overgrown Ruins near the Nautiloid Crash Site. These ruins are found along the beach but cannot be entered from there, requiring players to explore more of the area and find their way in from above.
Baldur's Gate 3: Overgrown Ruins Dungeon Guide (How to Get the Treasure From the Overgrown Ruins)
