Just pure imagination! Used photoshop to combine 2 pictures, took an hour to assemble. But browsing thru my photo collection on what to enter for this contest took almost forever. Just recently went into an underground river with my kids and even at just at the entrance of the cave that they were already so afraid. Maybe due to the urban legend that people don't go out of the cave alive and ghosts can be seen anywhere. I found the rock formation creepy that it can be made a halloween theme.