A world-class walk along the enchanted River Thames I like to doff my cap to the jaunty statue of Whistler by Battersea Bridge, gazing out at the river he painted with such verve. No one better captured its witching hour than the American artist, who wrote, "The evening mist clothes the riverside with poetry, as with a veil, and the poor buildings lose themselves in the dim sky, and the tall chimneys become campanili, and the warehouses are palaces in the night, and the whole city hangs in the heavens, and fairy land is before us." Many others would choose the sweep across Petersham Meadows from Richmond Hill: the only view in England to have been protected by an Act of Parliament (in 1902), meaning we see Turner's lush vista, rather than the havoc of a brutalist architect. Pub-touring friends love the conspiratorial Prospect of Whitby at Wapping, supposedly the site of the oldest river tavern in London. Chiswick has a fair claim, too: the river narrows and the city turns more pastoral, despite the hub of industry at Fuller's Brewery there, established in 1845 on a site where ale has been brewed since Cromwell's time. Some aspects of the view have even changed for the better; when Robert Gibbings published his charming river travelogue, Sweet Thames Run Softly (an account of a punt trip at the start of the Second World War), he wrote of that stretch: "The river is filthy... there were children bathing, swimming in water the colour of beer, with a sediment on its surface, thick enough to be the beginning of a new continent." Now the Thames is said to be the cleanest major river in all of Europe. I would bet my pocket compass that the true urban hiker would always plump for river over trees, for its music and moods, the rowing boats and barges, the swans, eels and salmon, and for the secrets it hides - the bodies and bones, the bicycles and jewels long-lost. Above all, there's the fact that the great cities" waterways represent the flow of history itself, with the golden past tucked away upstream, like a happy childhood, and the looming future always somewhere down current. Why else would the British have celebrated the Queen's Diamond Jubilee with a river pageant, knowing that in this rare Elizabeth we celebrate her Tudor predecessor and her penchant for gilded water vessels? Everyone feels a river's flow is as inexorable as time's, which is why Paolo Sorrentino's dazzling new film La Grande Bellezza - a paean to Rome's beauty and decadence - ends with a single, seemingly endless panning shot up the Tiber. We are all just tiny, inconsequential gnats when set against the great flow of Roman history. Rivers are the great arteries of cities, pumping commerce and visitors along their channels: when you walk their banks, this vitality is transmitted to you. This is even true along smaller veins and tributaries. On Sunday, I walked along the Regent's Canal from Islington to Little Venice through pouring rain, and strode past joggers, moorhens, houseboats, a dapper duo in a little motorboat and a nice lady in a floating teahouse who sold me a brownie. London never seems so alive as it is on the thronged South Bank, or on the Millennium Bridge over to the Tate, where the gleam of water feeds the glint in walkers" eyes. We British may not be boulevardiers, but we're born flâneurs of the river bank.