In the side of a mountain, you carve out a roof with your jackhammer so you can worship the gods. Basically, you've created a little alcove where you can set up an altar and worship like some kind of mountain ascetic.

What's the object of your worship? Soup (すう)! There's a whole pantheon of soup gods, and you've come to the mountains to spend your days worshipping each and every one of them.