To see a sand dune in your dream, signifies your desires to be sheltered from the bitterness of reality.
While sand itself can be an adverse dream, sand dunes are a different matter altogether. A sand dune represents protection as these are protected from distraction by law and this dream shows that you are longing for, or actively seeking, protection in your life. To understand what the protection you are seeking actually is you will have to look to the other symbols in the dream and correlate it with the sand dune symbol.