It's this website: https://mapgenie.io/sons-of-the-forest/maps/world

If you don't know how to use maps, here's a quick over oversimplified explanation: Just open your gps. And find something big, like a lake or a river (just something you can see on the map). And than locate that on the interactive map, and you know where you are on the map.

Just click on the located cave and you should see what's there like loot, mutants, cannibals and ext.


And yea that's it