The Gatehouse website record for Castell Trefadog

In the community of Llanfaethlu. In the historic county of Anglesey (Modern authority of Anglesey, preserved county of Gwynedd).

Very heavily-defended coastal site. Recent excavation revealed the foundations of C14 stone house inside an enclosure. An unusual site, perhaps akin to Penmaen Castle, Gower. Some have suggested a Viking origin for the site, others call it native welsh. Undergoing coastal erosion. In CARN listed as early medieval promontory fort, prehistoric coastal promontory fort and unknown fort.
A natural coastal knoll has been enhanced with a rampart and ditch to form a promontory fort. The knoll has been eroded by the sea on the north-west and north-east and only a near square area about 18m across remains of what may have been a rather larger enclosure. The 1.8m deep ditch on the south-east side takes advantage of a natural gully and on this side the rampart rises 3.4m from the ditch bottom. Slighter banks on the noth-east and north-west sides are probably old field boundaries. No finds are known from the site and its original date is unknown. It is perhaps most likely to be a later Prehistoric or Roman period fort. The traditional identification as a medieval earthwork castle ['Castell - site of': on OS County series 1st edition (Anglesey V.12 1889)] is perhaps unlikely. (Coflein)

The Ordnance Survey Map Grid Reference is SH29088590

Sources of information, references and further reading

This site's National Monument Record (Coflein) number is 95571
This site's County Historic Environment Record (formerly Sites and Monuments Record) number is 1 'grey' literature, such as watching brief reports, held by H.E.R.s is often poorly referenced and is unlikely to be recorded in this website.

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The information on this web page may be derived from information compiled by and/or copyright of the Royal Commission on the Ancient and Historic Monuments of Wales, the four welsh archaeological trusts and other individuals and organisations. All the sources given should be consulted to identify the original copyright holder and permission obtained from them before use of the information on this site for commercial purposes. I do not receive any income from this site and I fund it myself.
The bibliography owes much to various bibliographies produced by John Kenyon for the Council for British Archaeology, the Castle Studies Group and others.

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