In How the Grinch Stole Christmas, the town of Whoville is situated between a few drooping mountains. Here's an example taken from the movie:
The tip droops, and the mountains can rise either straight up, or as in this case, at an angle. I find this geographical feature fascinating, and I'd love to have mountains that droop as part of my world.
What geological history would it take to have mountains predominantly be of this type?