Top of the Cliffs

From King's Quest Omnipedia

In the official KQ2, this is the high plateau at the top of the unclimbable eastern mountains of Kolyma. An enchanter had turned Pegasus into a snake because he had refused to be his mount, and left him up on the mountain to act as a guardian of a moist, dirty, and empty cavern to the east of the plateau, where one of the magic keys was hidden.