Walking: Tales from the riverbank: In perfect silence, Paul Gosling follows a stretch of the Thames

THERE is a convention among walkers that as we pass each other we give a cheery 'hello' and a smile. It is used by serious ramblers and casual strollers alike, and is accepted throughout Britain. It is somehow typical of London that it refuses to comply.

Walking along the river Thames, other walkers avert their faces, pretend you do not exist, and wear a suspicious look if you say anything. But what the capital lacks in charm it sometimes compensates for in its oddities and attractions. This is especially true of the Thames river front as it meanders upstream from the City.

The Ramblers' Association publishes a guide to walking the Thames from the flood prevention barrier (east of Greenwich), to the river's source, near Cirencester. I followed a section of this, on the south bank tow-path from Putney Bridge to Kingston, a gentle 13- mile stroll.

Putney wears one of the capital's more enticing faces. A sequence of boat-houses, ranging from that of the London Rowing Club to Westminster School's, is a reminder that this is where the Boat Race begins. A security alert on the Tube had delayed me in crossing London, and my intended early start became late morning.

On the horizon were the sparkling new buildings of Hammersmith, all glass and reflected sun. But along much of the Thames good is sited next to bad, and I first had to pass by Fulham FC, ugly council flats - which renovation was doing little to improve, and gas holders.

For most of the walk between Putney and Barnes the sweet aroma of blossom and the gentle birdsong overhead blotted out the usual smells and sounds of London. The Leg O'Mutton reservoir, slightly set back from the tow-path, has been turned into a nature reserve. Built in 1838, it was used until 1960, but now contains 160 species of plants, and 70 types of birds, including herons, the great crested grebe and cormorants. Sadly, I saw nothing more exciting than a swan and a duck.

I stopped for a pleasant lunch at The White Hart, sitting in the sun on the terrace, looking out over the Thames, listening to the traditional pub sound of clicking dominoes indoors.

When I resumed my walk, heading past Mortlake, the surroundings became less attractive. An ugly old brewery towered over the river, bearing graffiti from an earlier age, witness to the campaign in favour of pirate radio.

The environment improved, with fine Georgian houses dominating the riverside, before it worsened again. Beyond Chiswick Bridge, the air became heavy with smoke belching from a crematorium. Next to it was the foul decay of the municipal rubbish tip. And that was followed by the noxious

smelling sewage works. I would have tried to follow the north bank if I had known how unpleasant the stretch would be.

Rows of beautiful houses and gardens lit up the opposite bank at Strand on the Green. The Kew pumping station tower shone in the sunlight. I considered walking through Kew Gardens, but pounds 4 seemed too expensive for a brief stroll, so I stayed on the riverbank.

The beautiful bridge at Richmond Lock was being renovated, and marked a drastic change in riverside character. From Kew to Richmond I saw hardly anyone. It was as if the Thames was a well- kept secret, rather than the country's most important river. But at Richmond Bridge it became a popular amenity.

More than that, the Thames had become a great marketing opportunity - with tea gardens, cafes, pubs, ice-cream sellers, and rowing boats for hire. Many people were sunbathing. At least this was one place that had anticipated the Independent's call for more open spaces and cafes.

But I preferred it when the path once more became a lonelier place. Suddenly, the river was again rural, and I passed another nature reserve. Here the people behaved more idiosyncratically. One man was metal-detecting in a field, while a couple had found a tiny stretch of beach for their deck- chairs.

The section is remote, with a couple of miles separating Richmond Bridge and the next crossing point by Teddington Lock. Those who want to cross at any other point use a small ferry, which only carries about 10 people.

When I reached Teddington Lock the change of character was almost complete - these were the rich London suburbs, so different from inner-city Wandsworth and Hammersmith where I started. From this point on, the river is non-tidal, and dominated by pleasure boats.

It was time for me to leave London. In truth, it was not a walk that matched the spectacular scenery and variety of a coastal path or hill- top ridge. But it was pleasant, showed me parts of London I had never seen, and highlighted those places I would like to revisit. It had even improved my opinion of London - despite all those sour faces of the other walkers.

The Thames Walk by David Sharp is published by the Ramblers' Association at pounds 2.95, available from the RA or through bookshops.

(Photograph omitted)