Level 1

Eagle Labyrinth (Or simply Level 1) is the first dungeon in The Legend of Zelda and, by extension, is the very first dungeon seen in the entire Zelda franchise.

Entrance to the Labyrinth
In both quests, the Eagle Labyrinth is found on an island which Link reaches by way of a bridge. The island is in the center of a lake, and no previous items are needed to go there. The entrance itself is inside one of the brown trees.

First Quest
The interior of this dungeon appears to be made of stone bricks, like most dungeons in The Legend of Zelda, with its primary color being teal. Since it is the first dungeon in The Legend of Zelda, it is often considered as being one of the easier and shorter dungeons in the game.

The main items of this dungeon in first quest are the Boomerang, guarded by a room full of Goriya, and a Bow, although it will not come equipped with arrows, forcing Link to purchase some from one of the shops in the Hyrule overworld. The boss of the dungeon is Aquamentus, who guards one of the Triforce pieces.

When viewed on a map, this dungeon appears to be in the shape of a bird, with the tip of its right wing being the room containing the dungeon's Triforce piece. The dungeon's name is an obvious reference to its shape.

Second Quest
The Eagle Labyrinth's entrance is in the same location as the one from the First Quest. The dungeon's layout, however, like that of most dungeons in the second quest of The Legend of Zelda, greatly differs in size and difficulty. The dungeon's walls and flooring are again teal in color.

The main item of this dungeon is reduced to only the Boomerang which is again guarded by a room of Goriya, and the Bow have been moved to another dungeon location. Aquamentus also returns as this dungeon's boss, guarding one of the Triforce pieces as before.

The most notable difference in the shape of this dungeon is that it is changed from the shape of an eagle into the shape of the letter E, sharing a common link with most second quest dungeon that use letters to make up a word. When the shapes of the Lizard Labyrinth (Letter Z), Eagle Labyrinth (Letter E), Manji Labyrinth (Letter L), Snake Labyrinth (Letter D), and Moon Labyrinth (Letter A) are listed in that order, they spell Zelda.

First Quest

 * Blue Keese
 * Stalfos
 * Small Gel
 * Red Goriya
 * Blade Trap
 * Wallmaster

Second Quest

 * Red Goriya
 * Blue Keese
 * Stalfos
 * Blue Goriya
 * Blade Trap
 * Small Gel
 * Moldorm
 * Blue Bubble
 * Wallmaster

Trivia

 * The Eagle Labyrinth and the Gnarled Root Dungeon from Oracle of Seasons have several similarities. The exterior of both dungeons is what appears to be a dead tree in a small island within a lake, and both dungeons have Aquamentus as the main boss.
 * In Norse mythology there is a dragon named Níðhöggr that gnarls on a root of Yggdrasil, compare with the fact that the boss of this dungeon is a dragon that lives in a tree based dungeon.