Bathophobia is the fear of depths in great volumes. It's seemingly just the fear of being overwhelmed, but by an actual physical thing. It's not the most common phobia, but it can be intense. The fear can be of the depths of the ocean, how huge a certain landscape is, or even the depths of something like a hallway. It's all lumped into the same fear: a fear of "depth."
The movie The Shining actually used this fear, along with bathmophobia, to prey on people's discomfort by shooting from a long distance away as the main characters did something on a stairway. The stairways always seem unclimbable and the son, Danny, would bike down seemingly endless hallways where danger could be at any point.
If you have a fear of depth, fear of the deep ocean, fear of giant heights, or a general fear of feeling small in an otherwise huge environment, then this list is definitely for you. Or not.