Cliff 
To dream that you are standing at the edge of a cliff implies that you are at an important crossroads in your life. You have a difficult decision to make, and you are fearful of choosing the wrong option. Perhaps you finally comprehend some previously misunderstood issue, or you have developed a different opinion.
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To dream that you or someone falls off a cliff represents your fears and hesitations about an issue or situation that you need to tackle in the future. You doubt your ability to overcome these obstacles.
Rocks
To dream of rocks may be associated with the enduring quality and stability as in the expression, 'solid as a rock.'
It may also signify making changes in your life to establish solid ground as you continue to build up and work on the attainment of your goals. On the other hand, rocks also mean conflict, sorrow, and being headstrong.
To dream of scaling a steep rock suggests hardship, difficulties, and fear of failure.
*See Stones
Hang Gliding
To dream of hang gliding indicates personal liberty and courage. Dreaming of hang gliding symbolizes belief in one's destiny. On the other hand, to dream that you crash a hang glider means a loss of faith and failure to commit.
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