Answer:
I am a cave full of bones and the house of a worm.
I like to twirl my body but keep my head up high. After I go in, everything becomes tight. What am I?
In Paris but not in France the thinnest of its siblings.
I have keys but no locks. I have space but no room. You can enter but can't go outside. What am I?
Good memory, skin like the sea. A great beast I am, yet vermin frightens me. What am I?
What never gets any wetter no matter how hard it rains?