What does Deuteronomy say about the location of Moses' grave?

Answer: No one knows where it is

The LORD buried Moses in a valley in Moab facing Beth-peor, and no one to this day knows the location of his grave.

“And He buried him in a valley in the land of Moab facing Beth-peor, and no one to this day knows the location of his grave.”— Deuteronomy 34:6 (BSB)