Het Palace of Westminster is the meeting place of the House of Commons and the House of Lords, de twee huizen van het parlement van het Verenigd Koninkrijk. Commonly known as the Houses of Parliament after its tenants, het paleis ligt aan de Middlesex oever van de rivier de Theems in de City of Westminster, in het centrum van Londen. Zijn naam, die voortvloeit uit de naburige Westminster Abbey, may refer to either of two structures: de Old Palace, a medieval building complex that was destroyed by fire in 1834, and its replacement New Palace that stands today. For ceremonial purposes, the palace retains its original style and status as a royal residence.
The first royal palace was built on the site in the eleventh century, and Westminster was the primary London residence of the Kings of England until a fire destroyed much of the complex in 1512. After that, it served as the home of Parliament, which had been meeting there since the thirteenth century, and the seat of the Royal Courts of Justice, based in and around Westminster Hall. In 1834, an even greater fire ravaged the heavily rebuilt Houses of Parliament, and the only structures of significance to survive were Westminster Hall, the Cloisters of St Stephen’s, the Chapel of St Mary Undercroft and the Jewel Tower.
The subsequent competition for the reconstruction of the Palace was won by architect Charles Barry and his design for a building in the Perpendicular Gothic style. The remains of the Old Palace (with the exception of the detached Jewel Tower) were incorporated in its much larger replacement, which contains over 1,100 rooms organised symmetrically around two series of courtyards.