Dunstanburgh Castle. Dunstanburgh Castle is a 14th-century fortification on the coast of Northumberland in northern England, between the villages of Craster and Embleton. The castle was built by Earl Thomas of Lancaster between 1313 and 1322, taking advantage of the site's natural defences and the existing earthworks of an Iron Age fort. Thomas was a leader of a baronial faction opposed to King Edward II, and probably intended Dunstanburgh to act as a secure refuge, should the political situation in southern England deteriorate. The castle also served as a statement of the earl's wealth and influence, and would have invited comparisons with the neighbouring royal castle of Bamburgh. Thomas probably only visited his new castle once, before being captured at the Battle of Boroughbridge as he attempted to flee royal forces for the safety of Dunstanburgh. Thomas was executed, and the castle became the property of the Crown before passing into the Duchy of Lancaster. Dunstanburgh's defences were expanded in the 1380s by John of Gaunt, the Duke of Lancaster, in the light of the threat from Scotland and the peasant uprisings of 1381. The castle was maintained in the 15th century by the Crown, and formed a strategic northern stronghold in the region during the Wars of the Roses, changing hands between the rival Lancastrian and Yorkist factions several times. The fortress never recovered from the sieges of these campaigns, and by the 16th century the Warden of the Scottish Marches described it as having fallen into wonderfull great decaye. As the Scottish border became more stable, the military utility of the castle steadily diminished, and King James I finally sold the property off into private ownership in 1604. The Grey family owned it for several centuries; increasingly ruinous, it became a popular subject for artists, including Thomas Girtin and J. M. W. Turner, and formed the basis for a poem by Matthew Lewis in 1808. The Dunstanburgh Castle golf course was built near the property in 1900, and expanded by the castle's then owner, Sir Arthur Sutherland, in 1922. By the 1920s Sutherland could no longer afford to maintain the castle, and he placed it into the guardianship of the state in 1930. When the Second World War broke out in 1939, measures were taken to defend the Northumberland coastline from a potential German invasion. The castle was used as an observation post and the site was refortified with trenches, barbed wire, pill boxes and a mine field. In the 21st century the castle is owned by the National Trust and run by English Heritage. The ruins are protected under UK law as a Grade I listed building, and are part of a Site of Special Scientific Interest, forming an important natural environment for birds and amphibians. Dunstanburgh Castle was built in the centre of a designed medieval landscape, surrounded by three artificial lakes called meres covering a total of 4.25 hectares. The curtain walls enclose 9.96 acres, making it the largest castle in Northumberland. The most prominent part of the castle is the Great Gatehouse, a massive three-storey fortification, considered by historians Alastair Oswald and Jeremy Ashbee to be one of the most imposing structures in any English castle. Multiple rectangular towers protect the walls, including the Lilburn Tower, which looks out towards Bamburgh Castle, and the Egyncleugh Tower, positioned above Queen Margaret's Cove. Three internal complexes of buildings, now ruined, supported the earl's household, the castle constable's household and the running of the surrounding estates. A harbour was built to the south-east of the castle, of which only a stone quay survives. The site of Dunstanburgh Castle in north-east Northumberland was probably first occupied in prehistoric times. A promontory fort with earthwork defences was built on the same location at the end of the Iron Age, possibly being occupied from the 3rd century BC into the Roman period. By the 14th century, the defences had been long abandoned, and the land was being used for arable crops. Dunstanburgh formed part of the barony of Embleton, a village that lies inland to the west, traditionally owned by the earls of Lancaster. The origins and the earliest appearance of the name Dunstanburgh are uncertain. Versions of the name, Dunstanesburghe and Donstanburgh were in use by the time of the castle's construction, however, and Dunstanburgh may stem from a combination of the name of the local village of Dunstan, and the Old English word burh, meaning fortress. Dunstanburgh Castle was constructed by Thomas, the Earl of Lancaster, between 1313 and 1322.