Dream of roof

I was on top of a hill with my brother and his singing teacher. The hill was roof shaped so it was a sheer edge at each side and covered with green and white shrubbery and brambles. We were on a mini railroad track in small carts on the peak and it seemed to go on forever. The weird thing was that there was a xylophone playing in the background, it sounded like a sort of sinister nursery rhyme tune. The sky was overcast and slightly misty. I could not see what was at the bottom of the as it was misty.