The first mention of the original Castell Deudraeth was by Geraldus Cambrensis in 1188: "We crossed the Traeth Mawr and the Traeth Bychan. These are two arms of the sea, one large and one small. Two stone castles have been built there recently. The one called Castell Deudraeth belongs to the sons of Cynan and is situated in the Eifionydd area, facing the northern Mountains."
The present Castell Deudraeth is one of a series of nineteenth-century mock-castles strung along the north Wales coast. Its 1850s conversion was rather late for a Gothic castle-house, but the building was an expression of the owner's belief in his noble ancestry. Sited within the grounds of Portmeirion, on the Penrhyndeudraeth promontory, it is set upon a level site, with the ground rising to the rear and falling to the front between the Glaslyn and Dwyryd estuaries. The property is approached over the main driveway through the Portmeirion estate.
The whole is set with an adjacent gravel forecourt, with lawns to the front linking to a formal garden to the left or west. The whole is set in parkland, two large fields created by amalgamating several smaller fields at some time around 1850 to create what Clough called North Park and South Park known locally as Cae Dreif (Drive Field) and Cae Mawr (Big Field). Clough's plan for the garden dated 1911 is his earliest surviving drawing relating to what would become the Portmeirion estate. Unfortunately as this plan was never carried out it has not proved possible to implement it under current HLF regulations which only allow for existing buildings and gardens to be restored.
The purchase of Castell Deudraeth and its grounds in 1931 added substantially to the size of the Portmeirion Estate. Clough wished to protect the woods and farmland that surrounded his village from outside development, as he had done at Plas Brondanw five miles to the North East. Here he had added the Parc and Croesor Estate to his holding: "I added a couple of adjoining and very beautiful properties that include the twin mountain summits of Moelwyn and Cnicht and the seventeenth-century manor house of Parc, since they had been widely advertised as promising areas for mineral prospecting and development. Some day it is to be hoped, really informed and sympathetic State protection may make natural beauty less precariously dependent on private piety."Soon after aquiring Castell Deudraeth Clough wrote in his guide book "Portmeirion Still Further Explained", Fourth Edition, April 1939: "The park, lawns and terraced flower gardens [at Castell Deudraeth] have now been brought back to their last century perfection, whilst the Castle itself has been most thoroughly reconditioned, so that with its generous central heating, main water supply, electric light and many bathrooms, it rivals, and in some respects actually surpasses, Portmeirion itself as a place to stay at."
Both the Brondanw and Portmeirion estates are owned by the Second Portmeirion Foundation. Clough was concerned about their long term future and believed that being owned by a Charity would help to ensure their preservation for the enjoyment of future generations. In 1973 the whole of Portmeirion was given Grade II listed status and in 1993 the Portmeirion Estate was designated a Conservation Area. Recently, as part of the Heritage Lottery Fund's assistance with the restoration of Castell Deudraeth and its gardens landscape consultants Nicholas Pearson Associates were commissioned to draw up an HISTORIC LANDSCAPE SURVEY & RESTORATION PLAN which has been implemented with regard to the restoration of Castell Deudraeth's garden to recreate the original Victorian layout and plantings.
There is no charge for admission to Castell Deudraeth or its gardens.