Aurora Borealis
I was lucky enough to see it a few times from Iceland and Greenland. As a young pro rock climber of sorts I ended up spending quite some time near Nanortalik in Southern Greenland. Although the climbing was fucking ridiculously amazing one of the most memorable moments was sitting on the beach after 30 days of seeing no one, the northern lights above our heads with huge icebergs floating past us in the sound as we sipped on gin and tonic (with ice knocked of the iceberg bits that floated into the shallows).