The treasure cave is in the Dark Forest, but not near the burial grounds. Take a look at this screenshot of the
4 maps together, which give a rough sketch of the Dark Forest, with an X at the cave.
For more than a hint (the entrance is obscured from view; minor <span class='standouttext'>Spoiler : </span><span class='spoiler'>behind a tree</span>) check out;
Silver Armour and Treasure Maps
