Moroni notes that this hill, which was a sacred site to him, was the same Cumorah where his father, Mormon, had deposited the sacred plates.
We do not know whether this hill had any other significance to the Jaredites, but it may not be totally unreasonable to suggest that Ether, under the inspiration of the Lord, may have likewise secreted his plates away there in a similar manner as did Mormon (see verse 33).