Answer:
I am a cave full of bones and the house of a worm.
I have married many women but have never been married. What am I?
So cold damp and dark I am. To stay you would refrain yet those who occupy me do never complain.
I march before armies, a thousand salute me. My fall can bring victory, but no one would shoot me. What am I?
I have no voice but I can teach you all there is to know. I have spines and hinges but I am not a door. Once I’ve told you all I cannot tell you more.
Though not a plant, has leaves. Though not a beast, has spine. Though many wouldn't need this thing, It's more valuable than wine.