Chelsea to Tower Bridge

Broadcaster John Sergeant follows in the footsteps of Victorian pioneer photographer Francis Frith who, in the 1860s embarked upon a monumental mission to attempt to document every city, town and village in Britain. John travels the country to discover more about this extraordinary man and his team and the unique record they left behind. John finds out what's changed, what's stayed the same and what has gone forever, and along the way he takes his own photographs inspired by the image taken by a Frith cameraman.

Today, this round-Britain trip begins in London, where John will meet the first ever lady Chelsea Pensioner, find out about the real Eliza Doolittles who inspired My Fair Lady and descend deep under Tower Bridge to witness Victorian engineering at its most impressive.