Corfe Castle Corfe Castle is a fortification standing above the village of the same name on the Isle of Purbeck in the English county of Dorset . Built by William the Conqueror , the castle dates back to the 11th century and commands a gap in the Purbeck Hills on the route between Wareham and Swanage . The first phase was one of the earliest castles in England to be built using stone when the majority were built with earth and timber . Corfe Castle underwent major structural changes in the 12th and 13th centuries . In 1572 , Corfe Castle left the Crown ' s control when Elizabeth I sold it to Sir Christopher Hatton . Sir John Bankes bought the castle in 1635 , and was the owner during the English Civil War . His wife , Lady Mary Bankes , led the defence of the castle when it was twice besieged by Parliamentarian forces . The first siege , in 1643 , was unsuccessful , but by 1645 Corfe was one of the last remaining royalist strongholds in southern England and fell to a siege ending in an assault . In March that year Corfe Castle was demolished on Parliament ' s orders . Owned by the National Trust , the castle is open to the public and in 2010 received around 190 , 000 visitors . It is protected as a Grade I listed building and a Scheduled Ancient Monument . History . Royal castle . Corfe Castle was built on a steep hill in a gap in a long line of chalk hills , created by two streams eroding the rock on either side . The name " Corfe " derives from the Old English " ceorfan " , meaning ' a cutting ' , referring to the gap . The construction of the medieval castle means that little is known about previous activity on the hill . However , there are posthole s belonging to a Saxon hall on the site . The hall may be where Edward the Martyr was assassinated in 978 . A castle was founded at Corfe on England ' s south coast soon after the Norman Conquest of England in 1066 . The royal forest of Purbeck , where William the Conqueror enjoyed hunting , was established in the area . Between 1066 and 1087 William established 36 such castles in England . Sitting as it does on a hill top , Corfe Castle is one of the classic images of a medieval castle , however despite popular imagination , occupying the highest point in the landscape was not the typical position of a medieval castle . In England , a minority are located on hilltops , but most are in valleys ; many were near important transport routes such as river crossings . Unusually for castles built in the 11th century , Corfe was partially constructed from stone indicating it was of particularly high status . A stone wall was built around the hill top , creating an inner ward or enclosure . There were two further enclosures : one to the west , and one that extended south ( the outer bailey ) ; in contrast to the inner bailey , these were surrounded by palisade s made from timber . At the time , the vast majority of castles in England were built using earth and timber , and it was not until the 12th century that many began to be rebuilt in stone . The Domesday Book records one castle in Dorset ; the entry , which reads " Of the manor of Kingston the King has one hide on which he built Wareham castle " , is thought to refer to Corfe rather than the timber castle at Wareham . There are 48 castles directly mentioned in the Domesday Book , although not all those in existence at the time were recorded . Assuming that Corfe is the castle in question , it is one of four the Domesday Book attributes to William the Conqueror ; the survey explicitly mentions seven people as having built castles , of which William was the most prolific . In the early 12th century , Henry I began the construction of a stone keep at Corfe . Progressing at a rate of per year for the best part of a decade , the work was complete by 1105 . The chalk of the hill Corfe Castle was built on was an unsuitable building material , and instead Purbeck limestone quarried a few miles away was used . By the reign of King Stephen ( 1135 – 1154 ) Corfe Castle was already a strong fortress with a keep and inner enclosure , both built in stone . In 1139 , during the civil war of Stephen ' s reign , Corfe withstood a siege by the king . It is thought that he built a siege castle to facilitate the siege and that a series of earthworks about south - south - west of Corfe Castle mark the site of the fortification . During the reign of Henry II Corfe Castle was probably not significantly changed , and records from Richard I ' s reign indicate maintenance rather than significant new building work . In contrast , extensive construction of other towers , halls and walls occurred during the reigns of John and Henry III . It was probably during John ' s reign that the Gloriette in the inner bailey was built . The Pipe Rolls , records of royal expenditure , show that between 1201 and 1204 over £750 was spent at the castle , probably on rebuilding the defences of the west bailey with £275 spent on constructing the Gloriette . The Royal Commission on the Historical Monuments of England noted the link between periods of unrest and building at Corfe . In the early years of his reign John faced lost Normandy to the French , and in further building work at Corfe coincided with the political disturbances later in his reign . At least £500 was spent between 1212 and 1214 and may have been focused on the defences of the outer bailey . R . Allen Brown noted that in John ' s reign " it would seem that though a fortress of the first order might cost more than £7 , 000 , a medium castle of reasonable strength might be built for less than £2 , 000 " . The Pipe Rolls show that John spent over £17 , 000 on 95 castles during his reign spread ; he spent over £500 at nine of them , of which Corfe was one . Additional records show that John spent over £1 , 400 at Corfe Castle . One of the secondary roles of castles was to act as a storage facility , as demonstrated by Corfe Castle ; in 1224 Henry III sent to Corfe for 15 , 000 crossbow bolts to be used in the siege of Bedford Castle . Following John ' s work , Henry III also spent over £1 , 000 on Corfe Castle , in particular the years 1235 and 1236 saw £362 spent on the keep . While construction was under - way , a camp to accommodate the workers was established outside the castle . Over time , this grew into a settlement in its own right and in 1247 was granted a market and fair by royal permission . It was Henry III who ordered in 1244 that Corfe ' s keep should be whitewashed . Four years previously , he also ordered that the keep of the Tower of London should be whitewashed , and it therefore became known as the White Tower . In December 1460 , during the Wars of the Roses Edmund Beaufort and his army marched from the castle destined for the Battle of Wakefield . During the march the army split at Exeter so the cavalry could reach the north quicker , and on 16 December 1460 some of his men became embroiled in the Battle of Worksop , Nottinghamshire . Beaufort and the Lancastrians won the skirmish . Post - medieval . The castle remained a royal fortress until sold by Elizabeth I in 1572 to her Lord Chancellor , Sir Christopher Hatton . Ralph Treswell , Hatton ' s steward , drafted a series of plans of the castle ; the documents are the oldest surviving survey of the castle . The castle was bought by Sir John Bankes , Attorney General to Charles I , in 1635 . The English Civil War broke out in 1642 , and by 1643 most of Dorset was under Parliamentarian control . While Bankes was in Oxford with the king , his men held Corfe Castle in the royal cause . During this time his wife , Lady Mary Bankes , resided at the castle with their children . Parliamentarian forces planned to infiltrate the castle ' s garrison by joining a hunting party from the garrison on a May Day hunt , however they were unsuccessful . The Parliamentarians gave orders that anyone joining the garrison would have their house burned and that no supplies were to reach the castle . Initially defended by just five people , Lady Bankes was able to get food through and swell the garrison to 80 . The Parliamentarian forces numbered between 500 and 600 and began a more thorough siege ; it went on for six weeks until Lady Bankes was relieved by Royalist forces . During the siege the defenders suffered two casualties while there were at least 100 deaths among the besieging force . The Parliamentarians were in the ascendency so that by 1645 Corfe Castle was one of a few remaining strongholds in southern England that remained under royal control . Consequently was besieged by a force under the command of a Colonel Bingham . One of the garrison ' s officers , Colonel Pitman , colluded with Bingham . Pitman proposed that he should go to Somerset to and bring back a hundred men as reinforcements , however the troops he returned with were Parliamentarians in disguise . Once inside , they waited until the besieging force attacked before making a move , so that the defenders were attacked from without and within at the same time . Corfe Castle was captured and Lady Bankes and the garrison were allowed to leave . In March that year , Parliament voted to slight ( demolish ) the castle , giving it its present appearance . In the 17th century many castles in England were in a state of decline , but the war saw them pressed into use as fortresses one more time . Parliament ordered the slighting of many of these fortifications , but the solidity of their walls meant that complete demolition was often impractical . A minority were repaired after the war , but most were left as ruins . Corfe Castle provided a ready supply of building material , and its stones were reused by the villagers . After the restoration of the monarchy in 1660 , the Bankes family regained their properties . Rather than rebuild or replace the ruined castle they chose to build a new house at Kingston Lacy on their other Dorset estate near Wimborne Minster . The first archaeological excavations were carried out in 1883 . No further archaeological work was carried out on the site until the 1950s . Between 1986 and 1997 excavations were carried out , jointly funded by the National Trust and English Heritage . Corfe castle is considered to be the inspiration for Enid Blyton ' s Kirrin Island , which had its own similar castle . Current status . In the 1980s , Ralph Bankes bequeathed the entire Bankes estate to the National Trust , including Corfe Castle , much of the village of Corfe , the family home at Kingston Lacy , and substantial property and land holdings elsewhere in the area . In the summer 2006 , the dangerous condition of the keep caused it to be closed to visitors , who could only visit the walls and inner bailey . The National Trust undertook an extensive conservation project on the castle , and the keep was re - opened to visitors in 2008 , and the work completed the following year . During the restoration work , an " appearance " door was found in the keep , designed for Henry I . The National Trust claims that this indicates that the castle would have been one of the most important in England at the time . The castle is a Grade I listed building , and recognised as an internationally important structure . It is also a Scheduled Monument , a " nationally important " historic building and archaeological site which has been given protection against unauthorised change . The earthworks known as " The Rings " , thought to be the remains of a 12th - century motte - and - bailey castle built during a siege of Corfe are also scheduled . In 2006 , Corfe Castle was the National Trust ' s tenth most - visited historic house with 173 , 829 visitors . According to figures released by the Association of Leading Visitor Attractions , the number of visitors in 2010 had risen to nearly 190 , 000 . Layout . Corfe Castle is roughly triangular and divided into three parts , known as enclosures or wards . Enclosed in the 11th century , the inner ward contained the castle ' s keep , also known as a donjon or great tower , which was built partly on the enclosure ' s curtain wall . It is uncertain when the keep was built though dates of around 1100 to 1130 have been suggested , placing it within the reign of Henry I . Attached to the keep ' s west face is a forebuilding containing a stair through which the great tower was entered . On the south side is an extension with a guardroom and a chapel . The two attachments postdate the construction of the keep itself , but were built soon after . To the east of the keep within the inner ward is a building known as the Gloriette . Only ruins are left of the Gloriette which was probably built by King John . The remains of the west bailey , the stone wall with three towers , date from 1202 – 1204 when it was refortified . It resembles the bailey of Château Gaillard , built by Richard the Lionheart in 1198 .