Metru Nui (Dome)

"Up ahead lay the Great Barrier, a cliff so high it vanished into the sky and so wide it encompassed the entire horizon."

- Narrator, Legends of Metru Nui

The Dome of Metru Nui, also known as the Great Barrier, is the massive dome that houses the Island City of Metru Nui.

History
The Great Barrier separated the Island City of Metru Nui from the rest of the Matoran Universe with only six gates open to access the City of Legends. During Makuta Teridax's struggle for power in Metru Nui, he disguised himself as the city's leader, Turaga Dume, and sent most of the members of the Toa Mangai to shut the gates. Unknown to the Toa Mangai, the Dark Hunter Eliminator, hired by Teridax, was stationed at the Barrier to kill the Toa. The Great Barrier was damaged during the Great Cataclysm, causing several holes and tunnels to open up in the wall. While fleeing the damaged City of Legends with six Matoran Spheres, the Toa Metru fought and imprisoned Teridax here, and then later came back to save the rest of the sleeping Matoran from the Visorak hordes by taking them through a series of tunnels to the Isle of Mata Nui above.

Landscape
The barrier has many cliffs along its' face, and a large door that connects Mangaia, Teridax's lair, to a ledge in the barrier that looks out over Metru Nui's Silver Sea. There are also several Sea Gates in the wall of the Great Barrier which, along with many underwater Chutes, go through the base of the barrier, leading to other parts of the Matoran Universe.

Appearances

 * BIONICLE 2: Legends of Metru Nui
 * BIONICLE Adventures 4: Legends of Metru Nui
 * BIONICLE Adventures 5: Voyage of Fear
 * BIONICLE Adventures 7: Web of the Visorak
 * BIONICLE 3: Web of Shadows
 * BIONICLE Adventures 9: Web of Shadows
 * BIONICLE: Maze of Shadows (Non-canonical Appearance)