London Guide
Mayfair
Along with neighbouring St James's and Marylebone, Mayfair emerged in the eighteenth century as one of London's first real residential suburbs. Sheep and cattle were driven off the land by the area's big landowners as small farms made way for London's first major planned development: a web of brick-and-stucco terraces and grid-plan streets feeding into grand, formal squares, with mews and stables round the back. Mayfair quickly began to attract aristocratic London away from hitherto fashionable Covent Garden and Soho, and set the westward trend for middle-class migration, which gradually extended to Kensington and Chelsea.
Nowadays, offices, embassies and lavish hotels outnumber aristocratic pieds-à-terre, yet the social cachet of Mayfair's luxury apartments and mews houses has remained much the same. When London's wealthier consumers moved west, so too did a large section of the city's commerce, particularly the more upmarket shops, which are still a feature of the area. The borders of Mayfair, in particular, remain among London's prime shopping streets, and it's here that Londoners mean when they talk of "going shopping up the West End". Piccadilly is no longer the fashionable promenade it once was, but a whiff of exclusivity still pervades Bond Street and its tributaries. Regent Street was created in 1812 as a new "Royal Mile" but took a while to catch on, while Oxford Street, to the north, didn't really come into its own until early last century, though it now surpasses the lot for the sheer mass of people fighting their way down it.
Sotheby's
Sotheby's, at 34–35 New Bond St 
020/7293 5000, 
www.sothebys.com , was founded in 1744 (though its pre-eminence only really dates from the last war). Viewing takes place from Monday to Friday, and also occasionally at the weekend, and entry to the galleries is free of charge, though without a catalogue (costing £10 or more) the only information you'll glean is the lot number. Thousands of the works that pass through the rooms are of museum quality, and, if you're lucky, you might catch a glimpse of a masterpiece in transit between private collections and therefore only ever on public display in the auction-house galleries. Anyone can attend the auctions themselves, though remember to keep your hands firmly out of view unless you're bidding.
Sotheby's is probably the least intimidating: there's an excellent café, and staff offer free valuations, if you have an heirloom of your own to check out. There's always a line of people unwrapping plastic bags under the polite gaze of valuation staff, who call in the experts if they see something that sniffs of real money. Christie's and Sotheby's, once quintessentially English institutions, are now under foreign control, with only Bonhams remaining British-owned. In 2002, Sotheby's and Christie's were found guilty of rigging the art market, defrauding sellers out of £290 million: Christie's escaped a fine because it confessed its sins, but Sotheby's was fined £12 million, and its former chairman jailed for a year.