WHAT lies behind London's theatreland? Behind the tacky neon strip joints and uber-cool bars of Soho?

Or the swanky hotels and penthouses lining Park Lane and Mayfair? Is Fitzrovia the new NoHo and who was the King of Quacks who once worked in Marylebone's Harley Street?

The West End has been the beating heart of London for two centuries or more. It is the centre of the capital's glamour, style and sophistication, a place of glitz, film launches, air-kissing celebrities, paparazzi, nightclubs and shopping. And it is often the first port of call for overseas visitors. With its theatres, landmarks and restaurants, it's not hard to see why Londoners and tourists alike are drawn here.

But as you stroll down Piccadilly, past the luxury hotels and brass nameplates of Mayfair, through Regent Street's grand parade of shops, up towards Oxford Circus, wend your way through the tight streets of Soho -- the centre of gay, as well as bohemian, London -- and push through the crowds at Leicester Square, there is little clue as to the murky past of many of its historic buildings.

Opulent parties were held here and scandals concealed: Nazi admirers, famous revolutionaries and eccentric writers all crammed within a few square kilometres of each other.

"Here Lenin, Stalin, Trotsky and Mussolini raged and raved, preached, practised and propogandised alongside a host of lesser-known figures," writes London tour guide and author Ed Glinert.

Glinert's new book, West End Chronicles, is a fascinating tome to read before visiting the area. Unlike other parts of the capital, such as the infamous East End of Jack the Ripper and the fictional villain Fu Manchu, there are few guides dedicated to the West End's rich history.

Situated west of the City of London, it was historically favoured by the rich elite as a place of residence because it was usually upwind of the smoke drifting from the crowded city.

It has, according to Glinert, four distinct areas: "The bright lights and red lights of Soho, the romantic mews of Mayfair, the elegant but rigid streets of Marylebone, and the chic enclaves of Fitzrovia."

Yet at one point "it was a nothing place ... a featureless land at the bottom of the Forest of Middlesex with no Thames to feed it. Just a stream, the Tyburn, helped map out the course of the area, running alongside today's Marylebone Lane."

Because the land lay near the palaces of St James's, Whitehall and Westminster, it was ideal for new development when the capital began bursting at the seams, particularly after the Great Fire of London in 1666 destroyed the old city. It was then that the West End became established.

The West End is an easy place to find. The four areas radiate from Oxford Circus. You can easily walk about the West End or simply hop on the Tube from stations such as Oxford Circus, Bond Street, Green Park, Piccadilly and Tottenham Court Road. Grab a London Underground map before you set out, and a trusty A-Z guide.

Marylebone (in the northwest) is home to Harley Street's private clinics, where the rich and famous have received exclusive medical treatment for the past century or more. Some locals still like to pronounce it as Marlybone.

In 1828, John St John Long, the so-called King of the Quacks, opened a practice for wealthy female clients at 84 Harley St. He would ask his clients to inhale from a long pink tube filled with a potent gas, noting how their resistance to his "massage sessions" lessened the more gas he used. After the death of two of his patients, he was convicted of manslaughter and fined pound stg. 250.

Today, Mayfair (in the southwest) is the place to discover discreet (and expensive) art galleries, embassies, small streets of elegant mews cottages, Piccadilly and its grand hotels, Hyde Park and its famous Speaker's Corner, where you can hear just about any radical philosophy or religious beliefs being debated (or sometimes just shouted at passers-by). In Grosvenor Square the squat US embassy is getting a security makeover. In 1968, 100,000 people gathered here to protest the Vietnam War.

Walk back from Mayfair past Gordon Ramsay's restaurant at Claridge's, a hotel where the guests have included the Italian fascist leader Benito Mussolini and US general Dwight Eisenhower (who said his room looked like "a goddamn fancy funeral parlour decorated in whorehouse pink").

The modern notion of shopping was born in Oxford Street: shopping, that is, for shopping's sake. Crowd-surf during the Christmas rush; angle through the hawkers and "chuggers" (charity muggers, hassling you to sign up to any number of good causes) and you will be among the living symbols of William Debenham, D.H. Evans and John Lewis. They arrived in the 19th century and changed the British high street forever.

Along with Harvey Nichols and Harrods, Selfridges, at 400 Oxford St, is one of the best-known stores in London. Gordon H. Selfridge was not a Brit at all but a self-made Chicago millionaire who arrived in town in 1909 determined to build England's first American superstore.

Everything was on an enormous scale: it had 130 departments, a post office, roof garden and soda fountain. Opening with the slogan "Why not spend a day at Selfridges?", it stunned staid Edwardian society. Within a week, a million shoppers had passed through its front doors. It was also the site for first television broadcast, in 1925.

To the south of Oxford Street is Soho. A curious mix of tattoo and piercing parlours, delicatessens, coffee shops, wine bars, massage parlours and mini-cab offices, as well as a media and gay hub, it takes its name from "So-ho", an old hunting cry used by the Duke of Monmouth. As Charles II's bastard son, Monmouth embodied the hopes of those who wanted a Protestant succession when others closer to the throne were Catholics. Sent into exile for links to a group of extremists, he returned to the capital without permission and in Soho was greeted by the ringing of church bells and celebratory bonfires.

When the unfortunate duke failed to seize the throne after his father's death, he was put to death in a terribly botched execution. It took three blows to remove his head and even then a knife had to be used to complete the decapitation.

Meanwhile, the eateries of Fitzrovia, to the northeast of Oxford Circus, are famous among the city's busy diners, ad execs and others working in the area. Named after the Fitzroy Tavern on Charlotte Street, it was a famous (or infamous) place for the creative likes of poet Dylan Thomas, artist Augustus John and writer George Orwell, who set several scenes of his dark-future novel Nineteen Eighty-Four in the local pubs.

By the 1950s all that had changed. A certain American trash writer by the name of L.Ron Hubbard had established the London Church of Scientology at 37 Fitzroy St, only a few doors down from the headquarters of the cult run by the notorious Aleister Crowley decades earlier. Nowadays you're more likely to find minor embassies, cloistered architects' offices and fabulous restaurants, such as Elena's L'Etoile, which has been around since 1904 and remains popular with the film crowd.

As Glinert concludes in his book, the West End has been home and host to some of the greatest revellers the planet has known: Oscar Wilde, Casanova, the scandalous George IV, comedian Tony Hancock (who later died in Australia), the artist Francis Bacon and more. It has become one of the few places in Britain where bohemian behaviour is expected.

A mere visit won't turn you into a bacchanalian monster, but it does everyone good to walk on the wild side once in a while.

Checklist
West End Chronicles: 300 Years of Glamour and Excess in the Heart of London by Ed Glinert (Penguin). Glinert is also the author of The London Compendium: A Street-by-Street Exploration of the Hidden Metropolis and the forthcoming London's Dead.

This story first appeared in The Australian © 2008.

Illustration: Tom Jellett