The Seven Golden Keys are magical keys that hold immense magical powers. In the The Magician King, the keys were used to open a door at The End of The World of Fillory, serving as a backdoor from where magic could flood again in case it ever was shut down by the Old Gods. In Season 3 of the SYFY Adaptation, the keys serve a similar purpose in the Quest for the Seven Keys, and are said to have the power to bring magic back.
