Between Richmond and the North Sea, thirty bridges cross the Thames. They carry people across a stretch of river 35 miles long, bringing together a population of nearly eight million. These extraordinary structures have been the making of London, Britain's capital, and according to Dan Cruickshank, Europe's greatest city.
Millions of Londoners cross these bridges every week. Most of them hardly give it a second thought. But bridges are much more than merely a means of transport - ways of getting from one place to another. They are also ways of linking the present to the past. London's Bridges are not just functional objects - they're also symbols, metaphors, which transform, connect and inspire. Some of them have vanished or been replaced - ghost-crossings of the past - but each of them is a clue to the city's hidden history - in some ways they are that history: a history that has lasted nearly four thousand years.
Dan's exploration of the mysteries of London's Bridges starts in the far east of London in the marshes of the Thames estuary, an eerie landscape which resembles the world of the river before the city of London and its bridges were built. The story then moves upstream to Vauxhall, where archaeologists are recording London's oldest crossing, built for religious reasons in the Bronze Age, three and a half thousand years ago. Thereafter it was 1500 years before the Romans built the first proper bridge, spanning the Thames near the site of today's London Bridge. That too was swept away, and it was only in the twelfth century that the famous London Bridge which entered legend, was built - the one covered with houses and shops which stood for six hundred years. We learn why it was 'falling down' as the nursery rhyme has it, and who was 'my fair lady'.
Old London Bridge presided over a very different London from today's a riverside world of water pageants and frost fairs when the whole river froze over. But from the eighteenth-century, London's growth required many more bridges, starting with Westminster Bridge in the political heart of England, which transformed London into a megacity of millions of people on both banks of the Thames. Eventually even historic London Bridge was replaced, with a proud structure which itself was dismantled, and is now to be found in a housing development in the Arizona desert.
The film continues with the engineering triumphs of the Victorian period at Hammersmith and Tower Bridge, and eventually the heroic Dartford Bridge which spans the river near the very marshes where Dan began his story. We conclude with the jewel-like Millennium Bridge, and Dan's hope that maybe one day, a true replacement for Old London Bridge will be built.