One of the most iconic images of London isn’t an architectural gem or a site steeped in centuries of history - it’s advertising space. The spot on the corner of Piccadilly Circus, between Shaftesbury Avenue and Glasshouse Street, is considered prime advertising real estate, with two million people passing by a week and space on the billboard selling for £4 million a year.

The lights have just been switched on, with a new giant billboard that uses cutting-edge recognition technology to deliver ads to passersby. Check out the video below to find out more.

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Piccadilly Circus is changing...

The site has been used for advertising since a Perrier sign was first erected in 1908, but if you’d walked past from it from 1990 to 2011 you would have seen adverts for two of Japan’s biggest technology brands - Sanyo and TDK.

In 2011 Sanyo vacated its space after 33 years because the owner wanted the neon sign to be replaced with one using LED technology. 

And on March 11 2015 TDK too discontinued its sign after 25 years, as it moved away from consumer goods and towards the business market. The strip occupied by TDK in the centre of the display was taken over by ITV.

In 2017 the huge new screen that is being installed will use "recognition technology" to target adverts at the nearby crowds.

The new developments are a world away from the earliest adverts on Piccadilly Circus that used incandescent light bulbs, before neon signs arrived in the 1940s – the first advertised Bovril. With the dawn of the 21st century, neon signs started to be replaced by LED screens, which allowed animated adverts.

Here’s a look at how the adverts at Piccadilly Circus have changed over the years:

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1919

Piccadilly Circus 1919

In this early photograph, the space isn’t being used for advertising at all, so you can actually see the buildings where the adverts now stand.

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1949

Piccadilly Circus 1949

Here you can see adverts for Bovril and Schweppes Tonic Water (which had a spot from 1920 to 1961), with Wrigley’s Chewing Gum on the building opposite. All the brands are still familiar to us today.

1956

Piccadilly Circus 1956

The famed billboard spot is covered up here for renovation work. Coca-Cola put its first sign up in 1954 – here it is next to the Guinness Time clock. The soft drink is still advertised on the spot today.

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1970

Piccadilly Circus 1970

Cinzano was hugely popular in the 1970s, so takes a prime spot and remained there until 1978, with Skol lager underneath.

1971

Piccadilly Circus 1971

Taken just a year later, what a difference colour brings to a photo! This shot is a great snippet of 1970s fashions, with cropped shorts and knee-length socks.

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2009

Piccadilly Circus 2009

In the 2000s there was a shift away from to neon to LED technology. Coca-Cola’s curved sign was erected in 2003 and is still in place today.

2014

Piccadilly Circus 2014

Hyundai Motors replaced Sanyo in 2011 with a computerised LED screen. The signs now are becoming more intelligent: the McDonald's sign installed in 2008 works with a smartphone app that lets you create a personalised character which appears randomly on the billboard.

2015

In 2015 the spot previously occupied by TDK was being used by ITV. Samsung was the only remaining tech brand to have an advertising spot on Piccadilly Circus.

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2017

The new 4K enabled screen is the largest of its kind in Europe. The new screen will keep the traditional six-panel 'patchwork' design, but will also have the ability to switch to a single giant display as needed.

Hidden cameras will be identify and analyse data gathered from foot and road traffic as it goes by, while the screen will also automatically respond to live weather, news, sports and social media updates.