Big Ben is the nickname for the Great Bell of the striking clock at the north end of the Palace of Westminster in London, England, and the name is frequently extended to refer also to the clock and the clock tower. The official name of the tower in which Big Ben is located was originally the Clock Tower, but it was renamed Elizabeth Tower in 2012 to mark the Diamond Jubilee of Elizabeth II.
The tower was designed by Augustus Pugin in a neo-Gothic style. When completed in 1859, its clock was the largest and most accurate four-faced striking and chiming clock in the world. The tower stands 96 m tall, and the climb from ground level to the belfry is 334 steps. Its base is square, measuring 12 m on each side. The dials of the clock are 6.9 m in diameter. All four nations of the UK are represented on the tower on shields featuring a rose for England, thistle for Scotland, shamrock for Ireland, and leek for Wales.
The tower is a British cultural icon recognized all over the world. It is one of the most prominent symbols of the United Kingdom and parliamentary democracy, and it is often used in the establishing shot of films set in London. The clock tower has been part of a Grade I listed building since 1970 and a UNESCO World Heritage Site since 1987.
Inside the tower is an oak-paneled Prison Room, which can only be accessed from the House of Commons, not via the tower entrance. It was last used in 1880 when atheist Charles Bradlaugh, newly elected Member of Parliament for Northampton, was imprisoned by the Serjeant at Arms after he protested against swearing a religious oath of allegiance to Queen Victoria. Officially, the Serjeant at Arms can still make arrests, as they have had the authority to do since 1415. The room, however, is currently occupied by the Petitions Committee, which oversees petitions submitted to Parliament.
On 21 August 2017, a four-year schedule of renovation works began on the tower. Modifications have included adding a lift, re-glazing and repainting the clock dials, upgrading lighting, and repairing roof tiles among other improvements. With a few exceptions, such as New Year's Eve and Remembrance Sunday, the bells are to be silent until the work is completed in 2022. In April 2022, the gantry supporting the scaffolding was removed, leaving the tower free of scaffolding.
According to Wikipedia