An early Christian monument, the Yarrow Stone (also known as the Liberalis Stone) lies in a small fenced enclosure, to the north of the A708, a half-mile (1 km) west southwest of Yarrow. Approximately 1.5m (5 feet) in height, the stone is thought to date from the early 6th century. Beneath were bone fragments and it had a Latin inscription on the eastern face but this has eroded over the years and is now difficult to read. This is translated as:
This the everlasting memorial.
In this place are the most famous Princes Nudus and Dumnogenus,
In this tomb lie the two sons of Liberalis.
The stone thus marks the burial place of two Christian British tribal leaders. It was discovered when the moor was first ploughed in the early 19th century and at first taken to the Duke of Buccleuch's residence at Bowhill for investigation but was soon returned to the spot where it was found.