Cerin Amroth
From Tolkien Gateway
Cerin Amroth was a mound in the heart of the ancient land of Lothlórien on which grew two rings of trees and a great tree with a white flet.[1] The hill was originally piled after the first millennium of the Third Age to be used as an outlook post for the growing shadow of Dol Guldur. Amroth, king of Lórien, later built a house on the flet to use as a home and the hill became named after him.[2]
It was here that Aragorn and Arwen plighted their troth centuries later, and where Arwen surrendered her life in Fourth Age 121.