A cyclist crosses a near-empty Westminster Bridge with the Houses of Parliament in the background in central London on April 9, 2020. - British Prime Minister Boris Johnson on Thursday began a fourth day in intensive care "improving" in his battle with coronavirus, as his government prepared to extend a nationwide lockdown introduced last month. (Photo by ISABEL INFANTES/AFP via Getty Images)
CNN  — 

Here’s some background information about Great Britain’s Houses of Parliament, located on the Thames River in London.

Facts

The meeting place of Great Britain’s bicameral legislature - composed of the House of Commons and the House of Lords - is also known as Westminster Palace.

Visitors are subject to airport style security checks.

Security technology, such as CCTV cameras and alarms, are used throughout the estate.

In addition to unarmed security officers, armed police officers are also on the premises.

Timeline (Selected)

11th century - The original palace is built.

1604-1605 - A group of English Catholics, including Guy Fawkes, plots to blow up Parliament to protest their treatment by the Protestants. However, the plot is uncovered and the conspirators hanged. November 5 is still celebrated in England as “Guy Fawkes Day,” when people celebrate with bonfires and fireworks and burn effigies of Fawkes.

October 16, 1834 - A fire destroys most of the building.

1840 - Construction begins on the current Houses of Parliament.

1852 - House of Commons is first used.

1870 - Construction is completed.

May 11, 1941 - The House of Commons chamber is destroyed in bombings during World War II. It is rebuilt by architect Sir Giles Gilbert Scott.

1950 - The reconstruction of House of Commons is complete.

1987 - The United Nations Educational, Scientific and Cultural Organization (UNESCO) designates the building as a World Heritage site.

2000 - Portcullis House, a new Parliamentary building, is completed.

February 2001 - Portcullis House officially opens.

June 18, 2015 - An independent committee issues a report outlining the need for extensive repairs throughout the historic complex. Issues that need attention include wiring problems, loose asbestos and rats. The principal architect at the Houses of Parliament tells the BBC, “Some of the facades are actually sinking and we’re going to have to investigate that very soon.”

March 22, 2017 - Khalid Masood plows a car through crowds on Westminster Bridge in central London before attempting to storm the Houses of Parliament in what police believe was an act of Islamist-inspired terrorism. Four people, including a police officer, are killed and scores injured before he is shot and killed by police.

August 14, 2018 - Several people are injured after a car crashes into security barriers outside the Houses of Parliament during rush hour. The driver is arrested on suspicion of terrorist offenses. He is later identified as Salih Khater, a 29-year-old UK national who emigrated from Sudan. Khater is later found guilty of attempted murder and sentenced to life imprisonment with a minimum of 15 years.

April 24, 2020 - Parliament publishes a report outlining each stage of work to be completed in the Palace of Westminster Restoration and Renewal Programme. This follows the October 8, approval of the Parliamentary Buildings (Restoration and Renewal) Act 2019.

April 21, 2020-July 22, 2021 - In response to the coronavirus pandemic, the Houses of Parliament put social distancing and other temporary measures into practice as needed. Measures are extended until July 22, the beginning of summer recess for the Houses of Parliament.

Characteristics

Designers/Architects - Sir Charles Barry along with Augustus Welby Pugin. Barry won a competition to be the architect.

There are four floors:
- Ground floor - Offices, river front houses, meeting rooms and dining halls.
- First floor - More dining rooms, Chambers of the House of Commons and House of Lords, and libraries.
- Second floor and Third floor - Committee rooms.

One end of the palace holds a private area for the speaker and on the other end, an area for the lord chancellor.

Made of limestone with an iron roof.

Three large towers, the Elizabeth Tower (316 ft. tall, holds the bell Big Ben), Victoria Tower (323 ft.), and Central tower (300 ft.)

The main entrance is called St. Stephen’s Hall, which leads immediately to the Central Lobby, or Octagon Hall. This area is open to the public.

Parliament has taken over nearby buildings as the need arose, including the Parliament Street Buildings and the Norman Shaw North and South buildings.