Because you didn't include any information about what was going on in your waking life at the time you had the dream or how you felt IN the dream, it's hard to say with any certainty what could have generated it. When interpreting a dream, it's always important to start with how you felt IN the dream. In this dream, it would seem as if you are having a great time with your grandfather. Grandfathers in dreams can either be literal, meaning the dream relates to a specific situation with your grandfather, or symbolic. Grandfathers are often wisdom figures in dreams. The setting of your dream provides another clue. Cliffs in dreams often represent precarious places or situations in waking life. However, there is no indication from your description that you are afraid. In this case, the cliff may represent the end of something in your waking life where you are also high up, which is a symbol that represents perspective and the ability to see or imagine the future. Sunsets are also metaphors for the end, literally of a day, but in dream-speak it could mean the end of a project or a stage in your life. The symbol of enjoying a cigarette together would seem to support a conclusion that you relaxing at the end of some major event or effort in your waking life. The fact that your grandfather is there with a full head of hair reflects your connection to him as a younger, more vibrant man... perhaps, he went through something similar in his life(?)
Here are links to the full definitions of symbols in your dream on this website:
cliff:
dreamdoctor.com/dream-dictionary/definitions/cliff.html
high up:
dreamdoctor.com/dream-dictionary/definitions/high-up.html
Please share what was going on in your life at the time of the dream that would generate such a positive and reflective dream.
