THE River Thames is the perfect place to spend a summer's day on or off the water. The stretch of river from Henley-on-Thames to Windsor is delightful, passing through gorgeous Chiltern countryside, pretty villages and historical beauty spots.

Whether you walk or travel by boat, you could begin at Henley and travel the length of the Royal Regatta course through the meadows to Temple Island, then by Hambleden with its lock and weir, Hurley and Bisham to Marlow which some say is the most delightful stretch of all.

On to Bourne End and Cookham, beloved of artist Stanley Spencer, catch a glimpse of Cliveden and its riverside cottage, setting of the notorious Profumo affair, then on to Maidenhead to recall its Edwardian heyday when the river here was packed with day trippers from London.

The riverside houses and landscaped gardens become more grand as Windsor Castle comes into view, high on the last chalky outcrop of the Chilterns.

Windsor is a good place to begin a day out on the river. Take a relaxing river cruise with impressive views of Windsor Castle, Eton College and Runnymede, where King John signed the Magna Carta in 1215. Try your hand at rowing on the river. Navigate your own route in a motor launch or hire a small boat. You can even take a boating holiday and literally live on the Thames.

It's a whole new pace of life on the river. Allowing time for locks and sightseeing, the 100-mile stretch from Reading to Oxford and back could take you a week. That's either the perfect antidote to the daily rush of life, or a sure way to drive you crazy. Its 44 locks are the river's way of making sure you leave that hectic pace behind.

There's certainly nothing quite so relaxing as drifting slowly up or down the river watching the wildlife, waving to other craft and peering into people's back gardens often very beautiful gardens alongside enviable country houses. You're likely to see kingfishers diving, swans gliding by, herons stalking the shallows and great crested grebes showing off their plumage.

Landlubbers can still enjoy the Thames, of course, thanks to the 180-mile Thames Footpath which begins at its source near Lechlade and ends at London's Thames Barrier. Don't forget, riverside walks are always level so the walking is easy.

Dip into little sections most people have their favourites. Or you could walk the whole length of one of the world's most famous rivers.

There are guides which list accommodation options along the route for people who want to do it all in one go. Or you could walk it in bite-size chunks.

Robin Wallhouse, a High Wycombe accountant, did this with two friends one summer. He says: "We took the occasional Thursday off and walked the entire length in about 13 outings, walking on average 16 miles a day.

"How long it takes depends on your stamina and whether you're a sightseer or a mile gobbler.

"The scenery was splendid, even in London itself, apart from the area around Wandsworth. We found sufficient pubs and alehouses for lunch stops, though the price varied.

"I'd certainly recommend the Thames walk. It was a good opportunity to get away and spend time talking with friends as we walked."

If you visit Windsor don't forget that Eton is just over the bridge. A guided tour of Eton College gives a fascinating peep into the history and present activities of this amazing school, founded by Henry VI in 1440. Sit in an original classroom, see the grafitti of the great and the good, visit the exhibition and enjoy the college chapel which is simply beautiful.