Chetham's School, Manchester.
A caged library- hundreds of years old. They used to lock people in with the valuable books. It would make a great ghost story if they forgot to let someone out. They would just find a skeleton with cobwebs.
From abandoned farm houses scattered along back country dirt roads to those gaudy old Victorian Mansions in old horror movies, I love a well aged hovel. So much more beautiful because of its decay.