Looking at Belgravia's noble squares and elegant terraces it is difficult to believe that barely two centuries ago the area was a swamp infested at night by highwaymen and footpads, though during the day it was a pleasant place for a stroll - in 1711 Jonathan Swift recorded seeing haymakers working there, and the 'sweet smell of the flowery meads.'

The transformation from boggy place to an area worthy of Britain's elite was ordered by the landowners, the Grosvenor family, who brought in one of the great builders of the 19th century, Thomas Cubitt.

One of the reasons the area was waterlogged was the clay soil, so Cubitt had the clay dug out and fired into the bricks needed for the buildings. Then he had a canal dug from the Thames, so barges could bring in thousands of tons of earth from the digging of London's docks, which was used to raise the levels. The land was drained and River Westbourne covered over. It was a stunning engineering achievement.

The design by George Basevi, Benjamin Disraeli's cousin, was spacious and imposing. Belgrave Square extends over more than ten acres, and Eaton Square is nearly a third of a mile long. The linking boulevards are wide and elegant. The houses were faced with a plaster called stucco that could be readily formed into the ornate features of the Italianate style. The one person who didn't like it much was Cousin Benjamin, who said it 'contrived to be at the same time insipid and tawdry'. But Disraeli himself lived in Mayfair so he might have been prejudiced.

The area became the height of fashion almost immediately, with aristocrats like the Earl of Essex, the Duke of Bedford and Earl Grey (famous for the tea) rapidly moving in. A further boost was provided in the 1840s when Buckingham Palace was finally completed.

Belgravia soon became a by-word for upper-class luxury and style - it is no coincidence that the classic TV series Upstairs Downstairs was set there at 165 Eaton Place. However this address is fictitious as they properties only go to 108.

After the world wars, death duties and the servant shortage forced most of the nobility out of the area and many of the houses were converted into embassies and academic institutions. However, the Grosvenor Estate maintained strict control of the building work in order to maintain architectural integrity, even specifying the exact shade of magnolia that houses have to be painted.

As a result, when the world's super-rich began to adopt London as their international headquarters, Belgravia was their preferred location, especially Belgrave Square, Eaton Square and Chester Square, the latter becoming well known as the last home of Baroness Thatcher. Two other prime ministers lived in Belgravia - Stanley Baldwin and Neville Chamberlain.

Among the galaxy of famous former residents, by a strange co-incidence the creator of James Bond, Ian Fleming, and two of the most notable actors who portrayed the spy on the big screen, Sean Connery and Roger Moore, all lived in Belgravia.

The grand houses that had become offices began to be converted back into homes. Suddenly the palatial interiors were used for entertaining again, and the enormous spaces available were adapted for modern life such as media rooms, gyms, swimming pools and secure parking. Many of the houses still have the mews house behind, originally built to house the carriage and horses but now invaluable as a garage and staff accommodation.

Potentially one of the grandest mansions is owned by oligarch Roman Abramovich who bought two houses in Lowndes Square and received planning consent to raze behind the period facade to create one house of 28,000 square feet.

The new residents of Belgravia are attracted by the location, just west of Buckingham Palace. It is convenient for Westminster and the City, and also handy for Heathrow and the private airports at Northolt and Farnborough.
World-famous shops are on the doorstep, from Harvey Nichols, Harrods and the global brands of Knightsbridge to Peter Jones and the fashionable boutiques of the King's Road.

So it is little surprise that Belgravia remains as it was built, one of the most exclusive and expensive areas in the world.