Greatfish Isle

Greatfish Isle is an island of the Great Sea in The Wind Waker. Once the location of a peaceful village of Hyruleans and Jabun, it is now a horrific wreck after being demolished by Ganondorf. Jabun fled the island and headed for Outset Island. Now, the only residents are a Traveling Merchant and the Korok Linder.

Features
Despite its destruction, the island still holds two Heart Pieces, and is one of the recurring destinations of the Ghost Ship. One of the Pieces of Heart can be found in a small indent by flying with the Deku Leaf directly northwest from the small spiral island chunk atop where the Korok rests. The other Heart Piece is given to Link from the Merchant in exchange of the Shop Guru Statue.

Beneath the waves is a fragment of the Triforce, available after finding and opening the Triforce Chart from the Islet of Steel (which is located one square south).

Scrapped Dungeon Theory
It has been speculated that Greatfish Isle was the original location of The Wind Waker's supposed third Goddess Pearl dungeon, because it was the home of Jabun, the keeper of Nayru's Pearl. Since the Great Deku Tree safeguarded Farore's Pearl, and the sky dragon Valoo protected Din's Pearl, it only makes sense for the home of Jabun to exist in a temple-bound place so he too can supervise the care and safeguarding of Nayru's Pearl. However, this theory has not been confirmed by Nintendo, and must therefore be taken as mere fan speculation.

The evidence in favor of this is as follows:
 * There are interviews where the creators say that some dungeons were left out of the final game.
 * Greatfish Isle, Fire Mountain, and Ice Ring Isle are marked on the full map of the Great Sea, where the only other islands that are marked are the most plot-important ones: islands with towns (Outset Island and Windfall Island) and islands with dungeons (Dragon Roost Island, Forest Haven, Tower of the Gods, Forsaken Fortress, Headstone Island, and Gale Isle). The implication is that at the time the map was made, Fire Mountain, Ice Ring Isle, and Greatfish Isle were considered equally important.
 * When connected by lines, Dragon Roost Island, Forest Haven, and Greatfish Isle form a large triangle; the three Triangle Isles, when connected by lines, creates a smaller triangle attached to the larger one - the entire image created is that of the Triforce, and the Tower of the Gods exists at the dead center of the symbol. An image of this can be found on the pirate ship, in Tetra's quarter. This adds further evidence to the theory, as both Forest Haven and Dragon Roost Island are home to temples.

Trivia

 * Greatfish Isle's German name, Ichthusk, comes from the Greek word,, meaning "fish".