These fountains had their names from two individuals, Dwy Fawr and Dwy Fach, who escaped from the Deluge, when all the rest of the human race were drowned, and the passing of the waters of the two fountains through the lake, without being confounded with its flood, is emblematic of the salvation of the two individuals from the Deluge, of which the lake is a type.
Dinas Bran, which crowns the top of the mighty hill on the northern side of the valley, is a ruined stronghold of unknown antiquity.

The name is generally supposed to signify Crow Castle, bran being the British word for crow, and flocks of crows being frequently seen hovering over it.

It may, however, mean the castle of Bran or Brennus, or the castle above the Bran, a brook which flows at its foot.
Dinas Bran was a place quite impregnable in the old time, and served as a retreat to Gruffydd, son of Madawg from the rage of his countrymen, who were incensed against him because, having married Emma, the daughter of James Lord Audley, he had, at the instigation of his wife and father-in-law, sided with Edward the First against his own native sovereign.

But though it could shield him from his foes, it could not preserve him from remorse and the stings of conscience, of which he speedily died.
At present the place consists only of a few ruined walls, and probably consisted of little more two or three hundred years ago: Roger Cyffyn a Welsh bard, who flourished at the beginning of the seventeenth century, wrote an englyn upon it, of which the following is a translation:-- "Gone, gone are thy gates, Dinas Bran on the height! Thy warders are blood-crows and ravens, I trow; Now no one will wend from the field of the fight To the fortress on high, save the raven and crow.".