A Royal Palace has existed at Westminster since the reign of Edward the Confessor in the eleventh century. Unfortunately, there are no surviving plans to show exactly what buildings there were, or where they were situated. Artists' reconstructions of the Palace and Abbey of this period show how close the river was to the main buildings, and where the surrounding buildings may have been located. What follows is an attempt to depict the evolution of the Palace at Westminster over the past 1000 years, from existing records. It is important to note however that not all the buildings shown existed in isolation.

Plans 1 to 6 show those parts of the building which still exist to this day, or those of which we have recorded documentation. Plans 7 and 8 are more detailed, and show the layout of the whole Palace as it would have looked in the eighteenth and early nineteenth century. The last two, plans 9 and 10 are accurate layouts of the New Palace of Westminster which still exists today.

When William the Conqueror's son, William Rufus, came to the throne in 1087 he decided to build a new Palace which would rival the size and splendour of Westminster Abbey. This Palace was never fully completed, but its major Hall still exists to this day and is now called Westminster Hall. It is this chamber which has since become the site of some of the most famous Trials in English History.

In the Twelfth Century the White Hall was built to the South of the Great Hall, a statue of Richard I now stands on its site. At the same period, another chamber was added to the North East corner of Westminster Hall.

During the reign of King Henry III in the Thirteenth Century, the Painted Chamber, the Queen's Chamber and the Queen's Chapel were added to the South East of the site, with access to the Garden and the River. It was probably within the Painted Chamber that the Death Warrant of Charles I was signed in 1649. By the end of the thirteenth century Westminster Hall had come to be the site of the Courts of Kings Bench, Chancery, and Common Pleas. All lay within the perimeter of the Hall, except the Court of Exchequer which was in a building adjoining the North of the West wall.

During the reigns of Edward II and III in the fourteenth century the Royal Chapel of St Stephen, begun by Edward I, was completed. When it was finished in 1348 Edward III founded the College of St Stephen there, including a cloister and living accommodation for the colleges' canons. St Stephen's Bell Tower was added at this time.

At the end of the fourteenth century King Richard II made some major structural changes to the Great Hall. The Norman Hall probably had two aisles of columns to support the weight of the roof. Richard removed these and added load bearing flying buttresses outside the East and West walls to support the new roof. The walls were heightened, the hammerbeam roof added, and huge new North and South windows were fitted. It was these structural changes which account for the vast and spacious hall which still stands today. A new entrance porch and two towers were added at the North Entrance.

In the early years of the sixteenth century the cloisters to St Stephen's Chapel were re-built. These provided covered access from the vicars houses and the Bell Tower to the Chapel.

Records of the Palace from the seventeenth century onwards are far more detailed, as exemplified by this plan of Westminster of the late eighteenth century. By this time the House of Lords and House of Commons had firmly established their respective chambers within the precincts of the Palace. The site was growing continuously, and various coffee shops, taverns and stalls had set up outside the main walls. As a result, in the 1790's The Stone Building was erected to tidy up the entrance to the House of Commons.

However, at the end of the eighteenth century George III announced that plans should be prepared 'for rendering the buildings of the House of Lords more commodious'. James Wyatt was appointed as the architect to redesign the King's Apartments, following his restoration of Westminster Abbey. Over a 12 year period all the post-medieval buildings were pulled down, and Wyatt's New House of Lords was erected. The Chamber was moved into the former Court of Requests, and a new Royal Entrance was designed. In the 1820's all the sheds and ale houses adjacent to the West Wall of Westminster Hall were demolished, and John Soane's new Law Courts were built creating a New west facade to the Palace, and a new entrance to the House of Commons.

In October 1834 the central section of the Palace of Westminster was almost entirely destroyed by a fire. The major sections to survive, which still exist to this day, were Westminster Hall with its courtrooms and the Chapel of St Mary Undercroft located underneath the ruins of St Stephen's Chapel. A competition was soon announced to design the New Palace of Westminster in the Gothic style. This was to keep it in harmony with those parts of the Palace which had withstood the fire. The winner was the architect Charles Barry.

The New Palace incorporates the old buildings but extends much further east towards the river than the old. The extra space was created by reclaiming land from the river. The New Palace is far larger and more symmetrical than the old. Barry opened up the original south wall of Westminster in order to incorporate the original medieval buildings in his New Palace. His plan also provides that from the Sovereign's throne at the south end of the House of Lords one can see directly to the Speaker's chair at the North end of the House of Commons, provided all the intervening doors are open.

The Palace of Westminster today has changed very little since the mid-nineteenth century. Barry's design has survived through two major wars, though the Chamber of the House of Commons was destroyed in 1941. In comparison to the damages of the 1834 fire, the building has since suffered only minor damage. Soane's law courts were demolished in the 1880s, and were replaced by Pearson's Westminster Hall Annexe, as the Royal Courts of Justice had moved to the Strand. The Commons Chamber was redesigned by Giles Gilbert Scott after its bombing in the Second World War, and new offices and an entrance for Members were constructed in the 1970s along the west side of Star Chamber Court. All modernisation of the building in the twentieth century has been carried out by the Parliamentary Works Directorate so as to blend in with Barry's overall design, and yet adapt it to the necessities of modern technology.