CASTELL-DINAS-BRAN, an ancient fortress at the Valle Crucis, in Denbigh; on a conical eminence 910 feet high, rising from the Dee in the north-eastern vicinity of Llangollen. It dates from very early times; was the chief seat of the lords of Yale and Bromfield; gave refuge to Gryffydd ap Madoc, at his alliance with Henry III.; and sustained a siege in the conflict between Owen Glendower and Lord Grey De Ruthin. Little more than substructions of it exist; but they show it to have been an oblong, 290 feet by 140, and very strong. Traces of entrenchments also are seen on the shoulders of the hill. The site commands extensive and very interesting views

(John Marius Wilson, Imperial Gazetteer of England and Wales (1870-72))