The Knowledge Towers were various of different towers, and they were located in Ko-Metru.
Their purpose was to act as a place for Ko-Matoran Scholars to work and study.
Nuju found his Toa Stone in the Knowledge Towers.
Also the Ko-Metru Great Disk was found in an icicle on a Knowledge Tower.
Knowledge Towers were grown by tossing a knowledge crystal (the size of a Matoran's hand) into a special cradles located in various spots in Ko-Metru. The crystal then grows in a rapid pace until it stands along the older towers.
Each tower contained living quarters, libraries, observatories, special storage areas, and laboratories.
- Comic 16: Toa Metru! - First appearance
- Comic 17: Disks of Danger
- Comic 20: Struggle in the Sky - (Mentioned only)
- BIONICLE 2: Legends of Metru Nui
- BIONICLE Adventures 1: Mystery of Metru Nui
- BIONICLE Adventures 2: Trial by Fire
- BIONICLE Adventures 3: The Darkness Below - (Mentioned only)
- BIONICLE Adventures 4: Legends of Metru Nui
- BIONICLE Legends 2: Dark Destiny - (Mentioned only)
- BIONICLE Legends 8: Downfall
- BIONICLE Legends 9: Shadows in the Sky - (Mentioned only)
- Nuju's Toa Metru Mini Promo CD
- Birth of a Dark Hunter - (Mentioned only)
- BIONICLE: Metru Nui - City of Legends
- BIONICLE: Rahi Beasts - (Mentioned only)
- BIONICLE: Encyclopedia
- BIONICLE: Encyclopedia Updated
- Search for Keetongu - (Non canon)