Rob Bell explores the extraordinary stories of four of London's most iconic bridges, uncovering the history behind how - and why - they were built. Rob explores the multiple versions of London bridge over the centuries and charts how each has shaped Britain's capital city, from the Romans who used it to control southern England, to the astonishing and raucous medieval bridge, designed by priests, inhabited by hundreds, and financed and managed by City merchants. As London and Britain grew wealthier, the pressure for a second bridge in the capital became irresistible. Financed by private capital, lotteries and grants, Westminster Bridge was built between 1739 and 1750 under the supervision of Swiss engineer Charles Labelye. By the mid-19th century, the bridge was subsiding badly and proving expensive to maintain. Finally, the history of Waterloo Bridge is uncovered and reveals an elegant bridge design by Rennie which is now almost entirely forgotten, as well as the invaluable work of women on the building of the current bridge during World War II.