The red pillar box is clearly one of the most iconic symbols of London and can be seen throughout London on so many streets. For so many years it has been a part of London as Royal mail was the main postal service.
Due to technology, mail has lessened as society embraces the internet and email exchange. In addition there are many other postal services in London which compete with Royal Mail.
these days, many are being sold off to private collectors as garden decoration and to remind people of times gone by.
the pillar box signifies London in so many ways; however I am not sure if it is a key part of society as it once was.