The Nine Maidens are stone monoliths that stand facing a tenth stone, that of the Fiddler. Legend has it that the maidens were turned to stone for the sin of dancing on the Sabbath. There are similar stories attributed to other stones in the UK (see Wrexham, Wales).

Castle-an-Dinas is said to be the site of King Arthur’s hunting lodge, from which he rode in the Tregoss Moor hunt. A stone in St. Columb allegedly bears the four footprints of his horse made whilst hunting. William of Worcester wrote the earliest written history during his visit to Cornwall in 1478. He noted that legend says that the fort was the place where Gorlois, Duke of Cornwall and husband of King Arthur's mother, died.

According to Coxe, in 1671 a man called John Trehenban (pronounced TREM-on) (1650–1671) of St. Columb Major, murdered two young girls and was sentenced to imprisonment in a cage on Castle an Dinas, and starved to death. This rock is still to be seen and local people used to say that if you ran around this rock fifty times you would hear his chains rattle… Or just feel very, very dizzy!