Skull mountain

In King Kong, the island is never mentioned by name and is located at approximately 12°S 78°E – somewhere off the coast of Periuk, Indonesia. There is a distinctive rocky knoll in the center of the island that is shaped like a human skull, which is referred to as "Skull Mountain".

According to the first film, the captain of a Norwegian barque discovered a canoe blown off course with only one native left alive. Before the native died, the captain of the barque was able to get a rough location of the island and some details on it, including its most distinctive feature - a huge wall built by the ancestors of the natives back when they had high civilization. When the protagonists of the picture arrive at the island and examine it they find, in addition to the expected superstitious natives, prehistoric creatures of all sorts and one extremely large ape, known by those on the island as "Kong".

Other than being the descendants of a high civilization, the ancestry of the natives is never explained.

In the sequel film The Son of Kong, Carl Denham returns to Skull Island when there was a mention of some treasure that was hidden there. He also encounters a large white gorilla who is the son of King Kong. Skull Island sinks into the sea during a powerful earthquake. Kong's son drowns while holding Carl Denham above the water. Denham survives unscathed, while the treasure is claimed by him and the other three survivors.

The term "Skull Island" is never used in the original films. In King Kong, only "Skull Mountain" is named, while in the sequel Son of Kong, its simply referred to as "Kong's island". In the novelization of King Kong by Delos Lovelace, it is called "Skull Mountain Island", but RKO referred to it as "Skull Island" in some of their publicity materials.