Purple Mountains
From Equestripedia, the Archives of Equestria!
The Purple Mountains was a region in Ponyland marked by Eminence, the living mountain who was also the king of the land.
History
Crunch was also created in the lands. The Volcano of Evil was presumably near the lands as well.
Near the mountains were the Rocklands, a temprary creation of Crunch that corrupted the Marshlands and other locations.