In Wales Illustrated in a Series of Views by Henry Gastineau, published in 1810, it states: "Near the town are some remains of an ancient fortress called Castell Cadwgan, thought to have been erected by king , about the year 1148."
Welsh Minstrelsy: Containing the Land beneath the Sea, published in 1824, states: "Just where [] juts out from the shore is an old fort, called ." .