Soak up some culture and beer

London's most stunning resource is also its most cheap and accessible - the river. A walk along the Thames from my home in Vauxhall, particularly at the height of summer, remains one of the finest days out London has to offer.

Personally, I'd bypass the free poultry and ponies at Vauxhall City Farm - and that other haven of south London wildlife, the uber-gay Vauxhall Tavern - and head for Tate Britain. Entry to the general collections are free and so, if you are a smug Tate member like me, is the current Art of the Garden exhibition (non-members £9.50).

From here, a short stroll along Millbank and back over Lambeth Bridge brings you to the charming Museum of Garden History, in the converted St Mary's Church beside Lambeth Palace. A "suggested" £3 donation buys access to all its horticultural historiana, a replica 17th-century knot garden and the grave of Captain Bligh, while a rejuvenating herbal cuppa in the vegetarian café costs just 75p.

Onward. Walk proudly past the crowds queuing up to pay £8.50 to get into the Saatchi Gallery (you've had your culture for free) or to shell out £11.50 for the London Eye (your pavement-level perambulations have shown you just as much of the city). The bookstalls under Waterloo Bridge may not be as glam as those on the Rive Gauche in Paris, but there are bargains to be had, plus the odd free performance inside or outside the National Theatre. Buy a copy of the Evening Standard (40p) in the theatre's bookshop. Take this to Studio 6, the bistro in Gabriel's Wharf, and peruse thoroughly on an outdoor table while quaffing a pint of Stella Artois (£2.95) and toying with a starter plate of meze (£4.50).

In fact, make that three pints, because from here on it gets a bit hectic. The throngs of riverbank perambulators between the National and the Conran restaurant-opolis at Butler's Wharf are now harassed at every step by the sort of mimes and living statues who prove conclusively that the term "street entertainer" is an oxymoron. Run past them as if you're in a Sam Peckinpah movie, repeatedly cocking and firing an invisible pump-action shotgun, and watch their frozen faces twitch.

By the time you reach Shakespeare's Globe and Tate Modern you will have had all the fun, exercise and culture anyone could possibly want for less than £20. It's time to get a bit reckless. The swift jaunt back to Millbank on the Damien-Hirst decorated Tate-to-Tate Boat costs £3.40 - you'll have blown your budget by 90p, but you'll end your day travelling in style.