>>33673423And ghosts.
"Cold iron" is historically believed to repel, contain, or harm ghosts, fairies, witches, and other malevolent supernatural creatures. This belief continued into later superstitions in a number of forms:
Nailing an iron horseshoe to a door was said to repel evil spirits or later, to bring good luck.
Surrounding a cemetery with an iron fence was thought to contain the souls of the dead.
Burying an iron knife under the entrance to one's home was alleged to keep witches from entering.
