Where would they be without it.

[V8Ian]

Mundane, essential and oh so interesting.

THE HISTORY OF THE LONDON UNDERGROUND (Full Documentary) - YouTube (http://www.youtube.com/watch?v=NuFy3j1bJUs&feature=youtu.be)

[Ausfree]

Hard to believe that London had 7 million residents before the end of the 19th Century!:o

[V8Ian]

I recall when I was in primary school in the mid '60s London had a greater population than all of Australia.