The shrine that holds answers to Diana's questions and Raya's chance of traveling the world.
The stone is an ancient Targonian relic that they use for certain rituals to protect the town which is powered by Raya's staff.
Raya and her mother pass down stories of the history of this artifact which in turn has been passed down to them for centuries and has deep ties to Lunari history carved into the stone (though Raya doesn't know them as the "Lunari" until Diana comes along).