The rock Carrock.
By the end of the third day of the month of April, Gandalf overcame the pass and went to the headwaters of the Anduin at the Carrock cliff.
In those days, it was also called Giad. Few remained those who remembered the terrible battle in which the supreme ruler of the giants was overthrown, and his head rolled down from the mountains and stuck here in the middle of the river, forming this very rock.