Climbing or seeing a mountain in a dream commonly reflects ambition and the size of the goal in front of you. The mountain's steepness can mirror how daunting the climb currently feels, while reaching even a modest ledge often points to progress you haven't given yourself credit for. Getting closer to the summit usually signals growing confidence.
He who is naturally well affected unto Astrology shall verily pronounce more certain Judgments. - William Lilly (1602.-1681.)