Westminster Hall is the oldest parliamentary building, dating back to 1097-1099. When it was built by William Rufus, it was the largest hall in Europe and helped establish Westminster as the ceremonial centre of the country. The first English Parliament met here in 1265.

Although it was rebuilt in the late 14th Century, with an impressive hammerbeam roof (b), the walls contain much of the original material. The hall was lucky to escape destruction by both the 1834 fire and World War II bombing with its vast stained glass arched window dominating one end still intact (c).

The hammerbeams were cleverly designed to hold the weight of the roof yet avoid the need for pillars. Earlier this century, when the roof was repaired, it was rumoured that tennis balls thought to have belonged to Henry VIII were found lodged inside.

For many years, the hall housed London's law courts and was also an important trading centre, with numerous shops and stalls.

But it has also been the setting for momentous legal and royal events, such as state trials. Thomas Moore, Charles I and the Gunpowder Plotters were all tried here, and it was the setting for coronation banquets.

Monarchs, consorts and distinguished statesmen are traditionally laid in state in Westminster Hall, the last one being Sir Winston Churchill in 1965.

Today, under a trial scheme, MPs use a Grand Committee Room off the hall (a) to hold debates in parallel with the House of Commons, while the main hall is often used for public ceremonies and displays.