Cloud Mountain is one of the secret citadels that housed a large colony of rabbits of the Resistance who referred to themselves as "The Heralds of the Mended Wood." It earned its name due to the mist that always forms a belt around its top.
The Secret Citadel of Cloud Mountain's symbol is a crest featuring two diamonds, the left one red and the other green, lying side-by-side. The green diamond represented The Green Ember, while the red one symbolized the Whitson Stone.
Cloud Mountain had many locations within it, including:
- The Savory Den
- King Whitson's Garden
- Light Hall
- Hallway Round, where was kept barrels of blast powder
- Village Green
- Great Hall
- Master Hall
- Mossy Porch
- Seven Standing Stones
- The Caves
The entrance into Cloud Mountain was a secret door in the back of the Savory Den, which opened into a tunnel that led into the main citadel. Out of all the rabbit citadels it seemed to have the largest population of civilians.
After escaping from Nick Hollow, Uncle Wilfred and Smalls take Heather and Picket to Cloud Mountain where they are befriended by Emma, Helmer, Maggie O'Sage, Lord Rake and many others. Heather and Picket are welcomed into the community by the initiation ceremony.
Cloud Mountain was the location of a meeting of all the lords of The Secret Citadels, at which event Lord Rake and Maggie O'Sage give speeches in the Master Hall that unite the somewhat reluctant lords of the citadels to oppose the Birds of Prey openly.
Heather and Picket return to Cloud Mountain when it is under siege by Morbin Blackhawk.