Castle Dore is said to have been the chief residence of King Mark of Cornwall. A 12th century poem by Beroul locates the fort in "Lancien," or the modern day farm of Lantian, outside of Golant in southern Cornwall.
Archeology has been unable to conform any King Arthur connection with Castle Dore. At sites such as Tintagel and Cadbury, there are indications of extensive refortification in the 5th and 6th centuries, the time of King Arthur. In addition imported Mediterranean pottery at these sites suggests a degree of prosperity. Excavations at Castle Dore in the 1930's failed to yield such evidence at that site. The stratiography (layers of earth) at Castle Dore have been destroyed by repeated ploughing, which makes dating of finds here difficult. It would appear that most of the construction at Castle Dore was done in the Iron Age peoples rather than by post-Romans such as Mark.
On the 31st August, 1644, Parliamentary forces seized Castle Dore for defence against the Royalists, but lost.
Castle Dore is, like the Tristan Stone, outside Fowey, near the small town of Golant. It is a little further north of the town than the Tristan Stone. A plaque has been put on the earthworks at Castle Dore by the Old Cornwall Society.