Flute

In Legend of Zelda

Allows you to warp to any dungeon you have cleared. If you are facing north or west, you warp to the next dungeon. If you are facing south or east, you warp to the dungeon before the one you are at.

In Adventure of Link

Acquired in the game's fifth palace, the flute allows Link to pass by what the villagers in the town of Nabooru call the River Devil. Once the flute is played, this troublesome roadblock disappears. Later in the game the instrument is used to make the sixth palace appear when played in the middle of the "Three Eye Rocks."