The vast world of “Final Fantasy VII” is full of secrets to discover. Some wonderful and amazing, some horrifying and destructive. Much like the underwater Sunken Gelnika, the Ancient Forest is another entirely optional and secret area, however in contrast to the sunken aircraft, the forest is located on an elevated plateau. Again much like it's fellow secret area, the Ancient Forest is full of treasure and ready to be placed into the hands of the heroes of “Final Fantasy VII”.
Unlike the Gelnika, however, which only had one way to access it via the submarine, the Ancient Forest has multiple avenues of reaching it. The first and perhaps most common way of getting to this forest is more indirect than anything. Just before the assault on Midgar at the end of disk two or any time during disk three, the player can find a giant black monster floating above a lake near the port city of Junon. Upon confronting this monster, a fight begins that seems to take place on the deck of the airship that the party travels around in, the Highwind. After the monster, Ultimate Weapon, has taken enough damage, it will flee from the battle. At this point, the party must trail the Weapon all across the Planet until it stops, and initiate battle again. After following this process several times, Ultimate Weapon will become weak enough and head to a spot over Cosmo Canyon for a final showdown.
Once the player has defeated Ultimate Weapon for the final time, the party will not only receive Cloud's ultimate weapon, Ultima Weapon, but they will also receive a path to the Ancient Forest. When Ultimate Weapon dies, it falls to the ground and explodes, causing part of the canyon that the Ancient Forest is sitting on to slant down, creating a path up to the top and into the forest.
The alternative way of accessing this forest is through the breeding of Chocobos. There are many types of Chocobos to breed, from ones that can cross rivers to ones that can cross oceans and even fly, there is also a Chocobo that can climb mountains, and that is the one that is needed to reach the Ancient Forest. However, breeding requires a lot of time and attention, so it is a lesser taken way to reach the Ancient Forest.