Official artwork of the Island

The island is the main setting where Cave Story takes place. It rests high above the surface world, and stays afloat by the power of the Core. While the exterior of the island appears rocky and cliff-like, inside are many intricate cave systems and secrets.

The island is inhabited by many Mimiga, whose species is gradually growing extinct because of the plans by The Doctor to control them.

If Quote falls or jumps off the island, it results in an instant death, with the message "You were never seen again...".

The island contains the destroyed remains of many killer robots, although a few robots are still functioning, such as the disarmed recon robots in the Labyrinth.

After the player destroys the Undead Core, the island can be seen falling to the surface in a short cutscene.