Well, there's the timezone boundary between Central and Eastern. And at some point the "hills" are tall enough to be called "mountains" ...
“at some point the ‘hills’ are tall enough to be called ‘mountains’”
I always chuckle when I hear “the mountain”. “Oh, they’re moving up on ‘the mountain’.” “They’re getting rain on ‘the mountain today.” “We’re lookin’ to build on ‘the mountain’.”
At first I would ask, “Which mountain?” Then I learned that every mountain is The Mountain. It’s all about context, and you just have to figure it out.