Introduction to the Palace of Westminster: The Palace of Westminster, also known as the Houses of Parliament, is one of the masterpieces of Gothic Revival architecture. It was listed as a World Cultural Heritage in 1987 . The building includes approximately 1,100 individual rooms, 100 staircases and 4.8 kilometers of corridors. Although today's palace was basically renovated in the 19th century, it still retains many historical remains from when it was first built, such as Westminster Hall (dating back to 1097), which is used today for major public celebrations, such as Display before state funeral, etc.