I heard someone refer to her book stack as “Hadrian’s Wall by my head at night.” I had to look it up.
The Wikipedia entry is linked above. I pulled photos from it, and, yes, I agree, it does look like a stack of books. In its day, before 122, it was much taller than it is now. Maybe people have gotten around to reading the books in the stack? Kidding. It looks like it would have been overwhelmingly huge in its time. Kind of like some books stacks I know.