Buttercup Mountain is a landform, on top of which the Crystal of Power lies. The Acorn Scouts enjoy visiting the mountain.
The mountain is covered in bright green grass. There are many patches of flowers and stumps on the terrain, in addition to pine and oak trees. There is a trail leading to the top of the mountain. The trail begins in a wooded area and ends at the Crystal of Power. Most of the trail is made of dirt. At the bottom of the mountain is a waterfall. A wooden bridge is located on top of it.
Buttercup Mountain has appeared in one episode of The Backyardigans: "Pablor and the Acorns" from season four.