The Great Forest is a jungle-like area. It houses a large variety of plant life and wildlife. There is a cavern in the middle of the forest which is the base of the large tree one can see in the camp. It is the home of Emerald Congalalas, Nargacugas, Shakalakas, King Shakalakas, Yian Garuga and Hypnocatrices. It first appeared in Monster Hunter Frontier.
There is a big tree in the middle of areas 6 and 5, as a variation of the map.
There is a Secret Area near Area 6 that is randomly accessible at High Rank and G-Lvl Guild Quests (You will start here on a High Rank or G-lvl Guild Quest if you have the Felyne Explorer food skill). It appears to be at the top of the giant tree in the middle of the forest.