Windsor Castle is the oldest royal residence to have remained in continuous use by the monarchs of Britain and is in many ways an architectural epitome of the history of the nation. Its skyline of battlements, turrets and the great Round Tower is instantly recognised throughout the world. The Castle covers an area of nearly thirteen acres and contains, as well as a royal palace, a magnificent collegiate church and the homes or workplaces of a large number of people ,including the Constable and Governor of the Castle, the Military Knights of Windsor and their families, etc.
The Castle was founded by William the Conqueror c. 1080 and was conceived as one of a chain of fortifications built as a defensive ring round London.
Norman castles were built to a standard plan with an artificial earthen mound supporting a tower or keep, the entrance to which was protected by an outer fenced courtyard or baily. Windsor is the most notable example of a particularly distinctive version of this basic plan developed for use on a ridge site. It comprises a central mote with a large bialy to either side of it rather than just on one side as was more than usual.
As first built, the Castle was entirely defensive, constructed of earth and timber, but easy access from London and the proximity of the Castle to the old royal hunting forest to the south soon recommended it as a royal residence. Henry I is known to have had domestic quarterswithin the castle as early as 1110 and Henry converted the Castle into a palace. He built two separate sets of royal apartments within the fortified enclosure: a public or official state residence in the Lower Ward, with a hall where he could entertain his court and the barons on great occasions, and a smaller private residence on the North side of the Upper Ward for the exclusive occupation of himself and his family.
Henry II was a great builder at all his residences. He began to replace the old timber outer walls of the Upper Ward with a hard heath stone found ten miles south of Windsor. The basic curtain wall round the Upper Ward, much modified by later alterations and improvements, dates from Henry II's time, as does the old part of the stone keep, known as the Round Tower , on top of William's the Conqueror's mote. The reconstruction of the curtain wall round the Lower Ward was completed over the next sixty years. The well-preserved section visible from the High street with its three half-round towers was built by Henry III in the 1220s.He took a keen personal interest in all his projects and carried out extensive works at Windsor. In his time it became one of the three principal royal palaces alongside those at Westminster and Winchester. He rebuilt Henry II's apartments in the Lower Ward and added there a large new chapel, all forming a coherently planned layout round a courtyard with a cloister; parts survive embedded in later structures in the Lower Ward. He also further improved the royal private apartments in the Upper Ward.
The outstanding medieval expansion of Windsor, however, took place in the reign of Edward III. His huge building project at the Castle was probably the most ambitious single architectural scheme in the whole history of the English royal residences, and cost the astonishing total of 50,772 pounds. Rebuilt with the proceeds of the King's military triumphs, the Castle was converted by Edward III into a fortified palace redolent of chivalry The stone base was and military glory, as the centre of his court and the seat of his newly founded Order of the Garter .Even today, the massive Gothic architecture of Windsor reflects Edward III's medieval ideal of Christian, chivalric monarchy as clearly as Louis XIY's Versailles represents baroque absolutism.
The Lower Ward was reconstructed, the old royal lodgings being transformed into the College of St George, and a new cloister, which still survives, built with traceeried windows. In addition there were to be twenty-six Poor Knights. Henry III's chapel was made over for their use, rebuilt and renamed St George's Chapel.
The reconstruction of the Upper Ward was begun in 1357 with new royal lodgings built of stone under the direction of William of Wykeham, Bishop of Winchester. An inner gatehouse with cylindrical towers was built at the entrance to the Upper Ward.Stone-vaulted undercrofts supported extensive royal apartments on the first floor with separate sets of rooms for the King and the Queen ( as was the tradition of the English royal palaces),arranged round two inner courtyards later known as Brick Court and Horn Court .Along the south side, facing the quadrangle, were the Great Hall and Royal Chapel end to end. Edward IY built the present larger St George's Chapel to the west of Henry III's.Henry YII remodelled the old chapel ( now the Albert Memorial Chapel) at its east end; he also added a new range to the west of the State Apartments which Elizabeth I extended by a long gallery .