Sir Charles Barry's Palace of Westminster includes several towers. The tallest is the 98 m (323 ft) Victoria Tower, a square tower at the south-western end of the Palace. The tower was named after the reigning monarch at the time of the reconstruction of the Palace, Queen Victoria. The tower is home to the House of Lords' Record Office, which, despite its name, has custody of the records of both Houses of Parliament. Atop the Victoria Tower is an iron flagstaff, from which the Royal Standard (if the Sovereign is present in the Palace) or the Union Flag is flown. At the base of the Victoria Tower is the Sovereign's Entrance to the Palace. The monarch uses this entrance whenever entering the Palace of Westminster for the State Opening of Parliament or for any other official ceremony.

Over the middle of the Palace lies the Central Tower. The Central Tower is 91 m (300 ft) tall, making it the shortest of the three principal towers of the Palace. Unlike the other towers, the Central Tower possesses a spire. It stands immediately above the Central Lobby, and is octagonally shaped. Its function was originally as a high-level air intake.

A small tower is positioned at the front of the Palace, between Westminster Hall and Old Palace Yard, and contains the main entrance to the House of Commons at its base, known as St. Stephen's entrance.

At the north-western end of the Palace is the most famous of the towers, St Stephen's Tower, the Clock Tower (often referred to as Big Ben) which is 96 m (316 ft) tall. The Clock Tower houses a large clock known as the Great Clock of Westminster. On each of the four sides of the tower is a large clock face. The tower also houses five bells, which strike the Westminster Chimes every quarter hour. The largest and most famous of the bells is Big Ben (officially, the Great Bell of Westminster), which strikes the hour. This is the third heaviest bell in England, weighing 13 tons 10 cwt 99 lb (about 13.8 t). Although the term "Big Ben" properly refers only to the bell, it is often colloquially applied to the whole tower.

The Chamber of the House of Lords is located in the southern part of the Palace of Westminster. The lavishly decorated room measures 14 by 24 m (45 by 80 ft). The benches in the Chamber, as well as other furnishings in the Lords' side of the Palace, are coloured red. The upper part of the Chamber is decorated by stained glass windows and by six allegorical frescoes representing religion, chivalry and law.
The upper part, or the viewing gallery, features a small curtain, around ten inches high. This was constructed in the 1920s to hide the ankles and lower legs of viewing women; fashion was becoming increasingly promiscuous, as they saw it, and the sight of bare legs was deemed unsuitable for Lords.

At one end of the Chamber are the ornate gold Canopy and Throne; although the Sovereign may theoretically occupy the Throne during any sitting, he or she attends only the State Opening of Parliament. Other members of the Royal Family who attend the State Opening use Chairs of State next to the Throne. In front of the Throne is the Woolsack, a backless and armless red cushion stuffed with wool, representing the historical importance of the wool trade. The Woolsack is used by the officer presiding over the House (the Lord Speaker since 2006, but historically the Lord Chancellor or a deputy). The House's mace, which represents royal authority, is placed on the back of the Woolsack. In front of the Woolsack are the Judges' Woolsack (a larger red cushion occupied by the Law Lords during the State Opening) and the Table of the House (at which the clerks sit).

Members of the House occupy red benches on three sides of the Chamber. The benches on the Lord Chancellor's right form the Spiritual Side and those to his left form the Temporal Side. The Lords Spiritual (archbishops and bishops of the established Church of England) all occupy the Spiritual Side. The Lords Temporal (nobles) sit according to party affiliation: members of the Government party sit on the Spiritual Side, whilst those of the Opposition sit on the Temporal Side. Some peers, who have no party affiliation, sit on the benches in the middle of the House opposite the Woolsack; they are accordingly known as cross-benchers.

The Lords' Chamber is the site of important ceremonies, the most important of which is the State Opening of Parliament, which occurs at the beginning of each annual parliamentary session. The Sovereign, seated on the Throne, delivers the Speech from the Throne, outlining the Government's legislative agenda for the forthcoming parliamentary session. The Commons do not enter the Chamber; instead, they watch the proceedings from the Bar of the House, just inside the Chamber. A similar ceremony is held at the end of a parliamentary session; the Sovereign, however, does not normally attend, and is instead represented by a group of Lords Commissioners.

Westminster Hall, the oldest existing part of the Palace of Westminster, was erected in 1097. The roof was originally supported by pillars but, during the reign of King Richard II, it was replaced by a hammerbeam roof designed by Henry Yevele and Hugh Herland. Westminster Hall is one of the largest halls in Europe with an unsupported roof; it measures 21 by 73 m (68 by 240 ft). An Essex legend has it that the oak timber came from woods in Thundersley, Essex.

Westminster Hall has served numerous functions. It was primarily used for judicial purposes, housing three of the most important courts in the land: the Court of King's Bench, the Court of Common Pleas, and the Court of Chancery. In 1873, these courts were amalgamated into the High Court of Justice, which continued to meet in Westminster Hall until it moved to the Royal Courts of Justice in 1882. In addition to regular courts, Westminster Hall also housed important state trials, including impeachment trials and the trial of King Charles I at the end of the English Civil War.

Westminster Hall has also served ceremonial functions. From the twelfth century to the nineteenth, coronation banquets honouring new monarchs were held here. The last coronation banquet was that of King George IV (1821); his successor, William IV, abandoned the idea because he deemed it too expensive. Westminster Hall has also been used for lyings-in-state during state funerals and ceremonial funerals. Such an honour is usually reserved for the Sovereign and for their consorts; the only non-royals to receive it in the twentieth century were Frederick Sleigh Roberts, 1st Earl Roberts (1914) and Sir Winston Churchill (1965). The most recent lying-in-state was that of Queen Elizabeth The Queen Mother in 2002.

In 1999 and 2003, the staff of the Palace were given special permission to return the Hall to its original purpose, by the holding of two Grand Parties there.

The two Houses have presented ceremonial Addresses to the Crown in Westminster Hall on important public occasions. For example, Addresses have been presented at Elizabeth II's Silver Jubilee (1977) and Golden Jubilee (2002), the 300th anniversary of the Glorious Revolution (1988), and the fiftieth anniversary of the end of the Second World War (1995).

Under reforms made in 1999, the House of Commons uses a specially converted room next to Westminster Hall (not the main hall) as an additional debating chamber. (Usually, however, the room is spoken of as a part of Westminster Hall.) The room is shaped like an elongated horseshoe; it stands in contrast with the main Chamber, in which the benches are placed opposite each other. This pattern is meant to reflect the non-partisan nature of the debates held in Westminster Hall. Westminster Hall sittings occur thrice each week; important or controversial matters are not usually discussed.

The Gentleman Usher of the Black Rod oversees security for the House of Lords, and the Serjeant at Arms does the same for the House of Commons. These officers, however, have primarily ceremonial roles outside the actual chambers of their respective Houses. Security is the responsibility of the Palace of Westminster Division of the Metropolitan Police, the police force for the Greater London area. Tradition still dictates that only the Serjeant at Arms may enter the Commons chamber armed.



Probably the most famous attempt to breach the security of the Palace of Westminster was the Gunpowder Plot of 1605. The plot was a successful conspiracy aiming to trick Roman Catholic insurgents into planning and preparing apparatus for an explosion in the Palace of Westminster during the State Opening of Parliament. If executed the explosion would have destroyed the palace, killing the Protestant King James I, his family, and most of the aristocracy. The plot was however always a trap, and through sabotage was discovered when a Roman Catholic nobleman, William Parker, 4th Baron Monteagle, received an anonymous letter warning him not to attend the State Opening. The authorities conducted a search of the Palace, discovered the gunpowder, as well as one of the conspirators, Guy Fawkes. The conspirators were later tried for high treason in Westminster Hall, and were hanged, drawn and quartered. Since 1605, the Yeomen of the Guard have conducted a ceremonial search of the Palace's cellars prior to each State Opening of Parliament.

The previous Palace of Westminster was also the site of a prime ministerial assassination in 1812. While in the lobby of the House of Commons, on his way to a parliamentary inquiry, Spencer Perceval was shot and killed by John Bellingham. Perceval remains the only British Prime Minister to have been assassinated.

On 17 June1974 a 20 pound (9 kg) bomb planted by the Provisional IRA exploded in Westminster Hall. In 1979 Airey Neave, a prominent Conservative politician, was killed by a car bomb as he drove out of the Palace's new car park. Both the Irish National Liberation Army and the Provisional IRA claimed responsibility for the murder; security forces believe the former were responsible. With rising concern about the possibility of a truck full of explosives being driven into the building (despite the effective cessation by that time of Northern Irish terrorism), a series of concrete blocks was placed in the roadway in 2003.

The Palace has also been the site of a number of acts of politically motivated "direct action". In 1970 a canister of tear gas was thrown into the Chamber of the House of Commons to protest against conditions in Northern Ireland. In 1978 manure was thrown. Concern about such attacks and a possible chemical or biological attack led to the construction of a glass screen across the Strangers' Gallery in early 2004.

The new barrier did not cover the front three rows, which are termed the "Distinguished Strangers' Gallery" and in May of that year protesters from Fathers 4 Justice attacked Prime Minister Tony Blair with flour bombs from this part. In September, five protesters opposed to the proposed ban on fox hunting disrupted the proceedings of the House of Commons by running into the Chamber.

Despite the recent security breaches, members of the public continue to have access to the Gallery. Visitors have to pass through metal detectors and their possessions are scanned. Large numbers of heavily armed police guard the building.