The first illuminated advert installed in Piccadilly Circus was in 1908 for Perrier. This grew into a hotchpotch of illuminated signs that surrounded the square and the area became synonymous with bright lights.
Rarely have these lights intentionally been turned off, they were switched off for the deaths of Winston Churchill and Lady Diana, they were off during the Blitz and more recently they were turned off to install a single state of the art LED screen that can choose content specific to environmental conditions.
It's estimated that 100 million people pass through Piccadilly Circus each year. Most of those people will consume content on mobile devices looking down, Piccadilly Circus is an exception to that, it’s impossible not to look up.