Alnwick Castle Alnwick Castle ( ) is a castle and stately home in the town of the same name in the English county of Northumberland . It is the seat of the Duke of Northumberland , built following the Norman conquest , and renovated and remodelled a number of times . It is a Grade I listed building and receives over 800 , 000 visitors per year . History . Alnwick Castle guards a road crossing the River Aln . Yves de Vescy , Baron of Alnwick , erected the first parts of the castle in about 1096 . It was built to protect England ' s northern border against the Scottish invasions and border reivers . The castle was first mentioned in 1136 when it was captured by King David I of Scotland . At this point it was described as " very strong " . It was besieged in 1172 and again in 1174 by William the Lion , King of Scotland and William was captured outside the walls during the Battle of Alnwick . Eustace de Vesci , lord of Alnwick , was accused of plotting with Robert Fitzwalter against King John in 1212 . In response , John ordered the demolition of Alnwick Castle and Baynard ' s Castle ( the latter was Fitzwalter ' s stronghold ) , however his instructions were not carried out at Alnwick . When the Vescy family became extinct , Alnwick Castle and the surrounding manor were bequeathed to Antony Bek the Bishop of Durham . The Percy family benefited from England ' s wars with Scotland ; through his military accomplishments Henry Percy , 1st Baron Percy ( 1273 – 1314 ) , enhanced his family ' s status in northern England . In 1309 he purchased the barony of Alnwick from Bek , and it has been owned by the Percy family , the Earls and later Dukes of Northumberland since . The stone castle Henry Percy bought was a modest affair , but he immediately began rebuilding . Though he did not live to see its completion , the building programme turned Alnwick into a major fortress along the Anglo - Scottish border . His son , also called Henry ( 1299 – 1352 ) , continued the building . The Abbot ' s Tower , the Middle Gateway and the Constable ' s Tower survive from this period . The work at Alnwick Castle balanced military requirements with the family ' s residential needs . It set the template for castle renovations in the 14th century in northern England ; several palace - fortresses , considered " extensive , opulent [ and ] theatrical " date from this period in the region , such as the castles of Bamburgh and Raby . In 1345 the Percys acquired Warkworth Castle , also in Northumberland . Though Alnwick was considered more prestigious , Warkworth became the family ' s preferred residence . The Percy family were powerful lords in northern England . Henry Percy , 1st Earl of Northumberland ( 1341 – 1408 ) , rebelled against King Richard II and helped dethrone him . The earl later rebelled against King Henry IV and after defeating the earl in the Battle of Shrewsbury , the king chased him north to Alnwick . The castle surrendered under the threat of bombardment in 1403 . During the Wars of the Roses , castles were infrequently engaged in battle and conflict was generally based around combat in the field . Alnwick was one of three castles held by Lancastrian forces in 1461 and 1462 , and it was there that the " only practical defence of a private castle " was made according to military historian D . J . Cathcart King . It was held against King Edward until its surrender in mid - September 1461 after the Battle of Towton . Re - captured by Sir William Tailboys , during the winter it was surrendered by him to Hastings , Sir John Howard and Sir Ralph Grey of Heton in late July 1462 . Grey was appointed captain but surrendered after a sharp siege in the early autumn . King Edward responded with vigour and when the Earl of Warwick arrived in November Queen Margaret and her French advisor , Pierre de Brézé were forced to sail to Scotland for help . They organised a mainly Scots relief force which , under George Douglas , 4th Earl of Angus and de Brézé , set out on 22 November . Warwick ' s army , commanded by the experienced Earl of Kent and the recently pardoned Lord Scales , prevented news getting through to the starving garrisons . As a result the nearby Bamburgh and Dunstanburgh castles soon agreed terms and surrendered . But Hungerford and Whittingham held Alnwick until Warwick was forced to withdraw when de Breze and Angus arrived on 5 January 1463 . The Lancastrians missed a chance to bring Warwick to battle instead being content to retire , leaving behind only a token force which surrendered next day . By May 1463 Alnwick was in Lancastrian hands for the third time since Towton , betrayed by Grey of Heton who tricked the commander , Sir John Astley . Astley was imprisoned and Hungerford resumed command . After Montagu ' s triumphs at Hedgeley Moor and Hexham in 1464 Warwick arrived before Alnwick on 23 June and received its surrender next day . The 6th Earl of Northumberland carried out renovations in the 16th century . After the execution of Thomas Percy , 7th Earl of Northumberland , in 1572 Alnwick castle was uninhabited . In the second half of the 18th century Robert Adam carried out many alterations . The interiors were largely in a Strawberry Hill gothic style not at all typical of his work , which was usually neoclassical . However in the 19th century Algernon , 4th Duke of Northumberland replaced much of Adam ' s architecture . Instead he paid Anthony Salvin £250 , 000 between 1854 and 1865 to remove the Gothic additions and other architectural work . Salvin is mostly responsible for the kitchen , the Prudhoe Tower , the palatial accommodation , and the layout of the inner ward . According to the official website a large amount of Adam ' s work survives , but little or none of it remains in the principal rooms shown to the public , which were redecorated in an opulent Italianate style in the Victorian era by Luigi Canina . Current use . The current duke and his family live in the castle , but they only occupy part of it . The castle is open to the public throughout the summer . After Windsor Castle , it is the second largest inhabited castle in England . Alnwick was the tenth most - visited stately home in England according to the Historic Houses Association , with 195 , 504 visitors in 2006 . Since the Second World War , parts of the castle have been used by various educational establishments : Firstly , by the Newcastle Church High School for Girls then , from 1945 to 1975 , as a teacher training college and , since 1981 , by St . Cloud State University of Minnesota as a branch campus forming part of their International Study Programme . Special exhibitions are housed in three of the castle ' s perimeter towers . The Postern Tower , as well as featuring an exhibition on the Dukes of Northumberland and their interest in archaeology , includes frescoes from Pompeii , relics from Ancient Egypt and Romano - British objects . Constable ' s Tower houses military displays like the Percy Tenantry Volunteers exhibition , local , volunteer soldiers raised to repel Napoleon ' s planned invasion in the period 1798 – 1814 . The Abbot ' s Tower houses the Regimental Museum of the Royal Northumberland Fusiliers . Other facilities open to the public including Knight ' s Quest ( formerly Knight ' s School ) , Dragons Quest , the Gift Shop , the Courtyard Cafe and restaurant ; The Sanctuary at the Castle . The castle is used as a stand in for the exterior and interior of Hogwarts in the Harry Potter films , which has led to an increase in public interest with Alnwick . Its appearance in the films has helped shape the public imagination regarding what castles should look like . Its condition contrasts with the vast majority of castles in the country which are ruinous and unfit for habitation . The wide angle images are computer generated . It has previously been a location used in " Becket " , " The Black Adder " ; " " and many others . Construction . The River Aln flows past the north side of the Castle . There is a deep ravine to the south and east , separating the castle from the town . By the 12th century , Alnwick Castle had assumed the general layout which it retains today . It is distinguished as one of the earliest castles in England to be built without a square keep . The castle consists of two main rings of buildings . The inner ring is set around a small courtyard and contains the principal rooms . This structure is at the centre of a large bailey . As the central block was not large enough to contain all the accommodations required in later centuries , a large range of buildings was constructed along the south wall of the bailey . These two main areas of accommodation are connected by a link building . There are towers at regular intervals along the walls of the outer bailey . About a sixth of the bailey wall has been reduced almost to ground level on the bailey side to open up views into the park . Stable and service yards adjoin the castle outside the bailey ; these would not have existed when the castle still had a military function . Alnwick Castle has two parks . Immediately to the north of the castle is a relatively small park straddling the River Aln which was landscaped by Lancelot Brown ( " Capability Brown " ) and Thomas Call in the 18th century ; it is known locally as The Pastures . Nearby is the much larger Hulne Park , which contains the remains of Hulne Priory . The castle is in good repair and used for many purposes . It provides a home for the present Duke and family and offices for Northumberland Estates , which manages the Duke ' s extensive farming and property holdings . Alnwick ' s battlement s are surmounted by carved figures dating from around 1300 ; historian Matthew Johnson notes that around this time there were several castles in northern England similarly decorated , such as Bothal , Lumley , and Raby . Alnwick Garden . Adjacent to the castle , Jane Percy , Duchess of Northumberland , has initiated the establishment of The Alnwick Garden , a formal garden set around a cascading fountain . It cost £42 million ( press release of 7 August 2003 ) . The garden belongs to a charitable trust which is separate from the Northumberland Estates , but the Duke of Northumberland donated the site and £9 million . The garden is designed by Jacques Wirtz and Peter Wirtz of Wirtz International based in Schoten , Belgium . The first phase of development , opened in October 2001 , involved the creation of the fountain and initial planting of the gardens . In 2004 a large ' tree house ' complex , including a cafe , was opened . It is deemed one of the largest tree houses in the world . In February 2005 , a poison garden , growing plants such as cannabis and opium poppy , was added . May 2006 saw the opening of a pavilion and visitor centre designed by Sir Michael Hopkins and Buro Happold which can hold up to 1 , 000 people . As of 2011 , there are still several areas to be completed , in order to fulfil the original design . Location filming . Alnwick Castle has been used as a setting in many films and television series .