It's probably London's most iconic feature, but how much do you really know about Big Ben? Read on for some trivia which may surprise you.
First things first
People often refer to Big Ben when they're talking about the clock tower attached to the Palace of Westminster.
Big Ben is the name of the largest bell, and even that's a nickname and not an official one. The tower is named the Elizabeth Tower (formerly the Clock Tower), a name it was officially given in 2012 to celebrate Queen Elizabeth II's diamond jubilee. If you're calling it St Stephen's Tower, you're well over a century behind the times.
The clock is simply known as the Great Clock.
More on that particular brand of pedantry here, but for the remainder of this article, we'll be using 'Big Ben' to refer to the whole package. Now we've got that out of the way, we'll move on...
Who is Big Ben named after?
There are several theories as to who the eponymous sizeable Benjamin could have been, but none were documented well enough to be proven right.
One idea is that it was named after MP Benjamin Hall, rumoured to have been a fairly round chap, and responsible for overseeing the latter stages of the rebuilding of the Houses of Parliament, including the installation of the bell.
Heavyweight boxer Benjamin Caunt is another contender. Watching him fight was a common pastime among MPs of the day, and he retired two years before the bell was installed.
The Elizabeth Tower has 334 steps over 11 floors up to the belfry (or 399 to the lantern).
Each clock face has a 7m diameter. The minute hand on each clock face is 4.2 metres long, and the hour hand is 2.7 meters long.
The main bell weighs 13.7 tonnes and is 2.7m in diameter. The four quarter bells are smaller, with different dimensions to enable them to hit different notes.
You can go inside
...but not for a while. Tours are suspended until 2020 while refurbishment work takes place. When they resume, assuming the long-standing system still operates, you'll need to contact your MP's office to sort it out for you. More info here.
There's a prison inside
A third of the way (or 114 steps) up inside the tower is the Prison Room, where MPs in breach of codes of conduct were imprisoned.
It was last used in 1880 when newly elected MP Charles Bradlaugh, an atheist, refused to swear allegiance to Queen Victoria on the bible. He was kept in the prison room overnight. There's even a pub named after him in Northampton.
There's a crack in the bell
Just two months after the bell first went into service in 1859, it was cracked. The hammer that was installed with it was roughly twice the size it should have been for a bell of that size. The damage was done — and the bell remains flawed to this day. A lighter hammer was fitted, and the bell was rotated slightly so that the hammer no longer hits the cracked section.
That bell wasn't even the original bell
The bell was famously cast at Whitechapel Bell Foundry — but that's not the whole story.
Originally, the contract to create the bell went to a company called Warners of Norton in Stockton-on-Tees. A 16.5 tonne bell was created and delivered to London before the clock tower was ready. For several months, the bell was tested outside the tower. It was working fine until the man who designed it, Edmund Beckett Denison, decided he wanted it louder so added a much larger hammer. Three weeks later the bell broke.
That bell was sent to Whitechapel Bell Foundry in pieces and melted down to create the new 13.5 tonne bell. Once this one was complete, it took 32 hours to winch it up the tower on its side.
Pennies for accuracy
When it was made, the clock was the most accurate in the world. It's kept accurate by some copper (pre-decimal) penny weights on the clock mechanism. Removing or adding a penny changes the clock's accuracy by two fifths of a second per day.
Three of the coins were replaced for the London 2012 Olympics.
It has its own Twitter account
@big_ben_clock tweets the relevant number of bongs on the hour, every hour. That's it. No replies. No retweets. Admittedly, it gets old pretty quickly — once you've seen 12 bongs, you've seen them all — yet the account still has an impressive 485,000 followers, despite following no-one.
BONG BONG BONG BONG BONG BONG BONG BONG BONG BONG BONG BONG— Big Ben (@big_ben_clock) August 4, 2016
See which other inanimate London objects have their own Twitter accounts.
Keeper of the Great Clock
A contender for best job title in London is Keeper of the Great Clock, a position currently held by Steve Jaggs (although if it were us, we'd prefer the title Big Ben's Boss).
As well as ensuring the clock is maintained, and overseeing the changing of the time twice a year, he also superintends a team of clockmakers, responsible for all the clocks in the Palace of Westminster.
When the bell has stopped:
In April 2013, the bell was stopped for the funeral of former prime minister Margaret Thatcher. Here are some of the other times that the chimes have been silenced.
The clock also stopped for 21 hours in 1941, when a worker who was carrying out repairs after a bombing raid dropped his hammer among the inner workings of the clock, forcing the clock to stop until the hammer was retrieved.
In 1949, a flock of starlings took up residence on the minute hand, slowing the movement and setting the time on the clock back by about five minutes.
Racing the BBC
You can hear the chimes of the bell on the radio before you hear it in real life, as we proved:
See also: our 2006 tour of the Clock Tower (as it was then called).