If it were findable by mundane or others of witchy they might be defiled. I would suggest very well hidden if not portable.

OOCly: I think Cults are always fun, as far as I know they exist in many different shades. I don't think there are factions per say to keep it organic. I would definitely chat with Abigail and Mavis to see what can be done. They are super when it comes to helping things get moving plot or story wise.