Elrond was one of the most wise and respected Elves in all of Middle-earth. He was the father of Arwen who forsook her immortal life to live with the mortal Aragorn.
He fought alongside Gil-galad and Elendil during the battle of the last alliance.
He brought up Aragorn to be a great king.
He discovered mysterious runes on a map owned by Thorin and company on their journey to the lonely mountain. Without the runes their quest would probably have ended in disaster before they even reached their destination.