The Great Forest is the first dungeon of the game you will visit, although you won’t be able to fully explore it right away. The game counts an area explored as long as you have stepped foot in it, so you don’t need to fully explore every inch of every area. The reason for this is because there are certain obstacles blocking your path, most notably the Elementum Pillars. There are four different kinds of these and you will unlock them as you play through the main story. In order to fully explore the Great Forest, you will need access to the Earth, Ice, and Lightning Elementum Pillars. There is a Fire one, too, but it only leads to a dead end.