God the Father appeared.

Our entire case as members of The Church of Jesus Christ of Latter-day Saints rests on the validity of this glorious First Vision. It was the parting of the curtain to open this, the dispensation of the fulness of times. Nothing on which we base our doctrine, nothing we teach, nothing we live by is of greater importance than this initial declaration. I submit that if Joseph Smith talked with God the Father and His Beloved Son, then all else of which he spoke is true. This is the hinge on which turns the gate that leads to the path of salvation and eternal life.  - Gordon B. Hinckley