Westminster Hall, the oldest existing part of the Palace of Westminster, was erected in 1097. The roof was probably originally supported by pillars, but during the reign of King Richard II, this was replaced by a hammer-beam roof, which allowed the original three aisles to be replaced with a single huge open space, with a dais at the end. Westminster Hall has the largest clear-span medieval roof in England, measuring 20.7 by 73.2 metres (68 by 240 ft).
Westminster Hall has served numerous functions. It was primarily used for judicial purposes, but has also served ceremonial functions, including banquets, coronations and lyings-in-state during state and ceremonial funerals. Such an honour is usually reserved for the Sovereign and for their consorts. The two Houses have presented ceremonial Addresses to the Crown in Westminster Hall on important public occasions.