London

Choosing where to sleep in London matters more than in almost any other British city, because the transport network is what you will spend your holiday inside if you get it wrong. A room that looks like a bargain in Zone 3 can cost you two hours a day and thirty pounds in fares, and a central room at a higher nightly rate often works out cheaper once you stop paying for travel and start walking home from dinner. The first question is not how much, but which part of the city you actually intend to spend your time in.

For a first visit of two or three nights, Zone 1 is worth the premium. Bloomsbury, Covent Garden and Victoria put the major sights within walking distance and let you drop bags at lunchtime and change before an evening out. If you are here for theatre, base yourself in the West End; for museums, South Kensington; for food and bars, Shoreditch or London Bridge. Families often do better slightly out - Greenwich, Richmond, Hampstead - where rooms are larger and parks are on the doorstep.

London rooms are small by international standards, and it is better to know that before you book. A comfortable double in a period townhouse conversion may be twelve or fourteen square metres. Compact-format hotels have made a deliberate model of this, trading floor space for a good bed, a proper shower and a central postcode at a fair price. At the other extreme, the grand hotels of Mayfair, Belgravia and the Strand offer real scale, service and history, and charge for all three.

Rates move a long way with the calendar. January and February are the cheapest months by a clear margin; the City is dear midweek and cheap at weekends, while the West End works the other way round. Booking six to eight weeks out and checking whether breakfast is included will save more than any amount of comparison shopping. Check the aspect too - a street-facing room on a bus route is a very different night's sleep from one over a courtyard.

The following is a starting point rather than a checklist. Most of these can be reached from each other on foot or by a short Tube ride, and several cost nothing.

• The British Museum - eight million objects in Bloomsbury, from the Rosetta Stone to the Sutton Hoo helmet, housed around Norman Foster's glass-roofed Great Court. Entry is free, the collection is far too large for one visit, and the quietest hours are the first and last of the day.
• The Tower of London - a working fortress since William the Conqueror, home to the Crown Jewels, the ravens and the Yeoman Warders whose tours are considerably better than the guidebooks suggest. Book a timed slot and arrive early, because the queue for the jewels builds fast.
• Tate Modern and the South Bank - the former Bankside power station turned free-entry modern art gallery, with the Turbine Hall commissions and a top-floor viewing level over the river. Walk east or west along the South Bank afterwards for street performers, the Globe and the National Theatre.
• Westminster and the Houses of Parliament - Big Ben, Westminster Abbey and Whitehall in a tight cluster. Parliament runs tours on Saturdays and during recess, and the Abbey holds the graves of monarchs, Newton, Darwin and half the English poets worth reading.
• The royal parks - Hyde Park, Kensington Gardens, Regent's Park, Green Park and St James's Park form a nearly continuous green corridor across the West End. St James's has the best view of Buckingham Palace, and Regent's Park has the rose gardens and the open-air theatre.
• Borough Market and Bermondsey - a wholesale market since at least the twelfth century, now the best place in London to eat standing up. Thursday to Saturday are the full trading days. Walk south afterwards along Bermondsey Street for the small galleries and the railway-arch breweries.
• Greenwich - the Cutty Sark, the Royal Observatory, the Painted Hall at the Old Royal Naval College and the view back over Canary Wharf from the top of the park. Arrive by river boat from Westminster or Tower Pier, which turns the journey into part of the day out.
• The Victoria and Albert Museum - decorative arts and design in South Kensington, next to the Natural History and Science Museums. All three are free, and the V&A's cast courts, fashion galleries and Friday late openings are the reason to choose it over the dinosaurs next door if time is short.

London has no single native cuisine, which is precisely the point. The oldest surviving dishes are working-class river food: pie and mash with liquor, the green parsley sauce that has outlived the eel trade that produced it, still served at M. Manze on Tower Bridge Road, trading since 1902. Jellied eels and whelks survive on a handful of market stalls. Fish and chips are done properly at the Golden Hind in Marylebone and Poppies in Spitalfields. The full English breakfast, the salt beef bagel from Beigel Bake on Brick Lane at three in the morning, and a Sunday roast in a proper pub are the other genuinely local rituals.

What the city really does is everyone else's food, cooked by people who grew up eating it. Brick Lane and Whitechapel for Bengali and Bangladeshi cooking; Southall and Tooting for Punjabi and Sri Lankan; Peckham for West African; Dalston for Turkish ocakbasi grills; Chinatown around Gerrard Street for Cantonese and increasingly for regional Sichuan and Hunan. Some of the best meals in London cost under fifteen pounds and come from a room with strip lighting and no reservation system.

At the other end, the city holds more Michelin stars than anywhere in Britain. Core by Clare Smyth in Notting Hill, The Ledbury, Restaurant Gordon Ramsay in Chelsea and Ikoyi near St James's sit at the top; Lyle's in Shoreditch, St John in Smithfield - the restaurant that reset British cooking around offal and nose-to-tail - and Brat in Shoreditch are the ones chefs talk about. Book weeks ahead.

The markets are worth a morning on their own. Borough for produce and prepared food, Maltby Street's Ropewalk on Saturdays, Broadway Market in Hackney, Brixton Village for Caribbean and Latin American, and Spitalfields for a mix of everything. For drinking, London's pubs are the point: the Lamb and Flag in Covent Garden, the Ye Olde Cheshire Cheese on Fleet Street, the Prospect of Whitby in Wapping and the Holly Bush in Hampstead all predate anything on the tourist trail. The city's brewing scene has grown up in the railway arches of Bermondsey - the so-called Bermondsey Beer Mile - where the taprooms open on Saturdays and you can walk between six or seven of them.

Camping in London is a real option, which surprises most people. Several full-service touring parks operate inside the M25, each on a rail or Tube connection that puts you in the centre within the hour. A pitch costs a fraction of a central hotel room and you get space and greenery, but you are camping in a city rather than the countryside - expect road noise, aircraft and light pollution rather than dark skies.

The terrain is easy. London sits in a shallow basin on the Thames and the sites are flat or gently sloping grass over gravel and clay. The clay matters after heavy rain, when pitches soften and awning pegs pull, so hardstanding is worth paying for between October and April. The sites on the Lea Valley gravels in the north drain considerably faster than those on London clay to the south.

The capital's weather is the mildest and driest in Britain, with roughly 600mm of rain a year and summer temperatures a couple of degrees above the national average thanks to the urban heat island. That is a mixed blessing under canvas: a July tent in London can be genuinely airless overnight, and the heat does not fall away after dark the way it does in open country. Bring more ventilation than you think you need and pitch in shade where you can.

On the legal position, be clear: wild camping is not permitted anywhere in Greater London. There is no equivalent of the Scottish right to roam, and the parks, commons, heaths and towpaths are all either byelaw-protected or privately owned. Sleeping out on Hampstead Heath, Epping Forest or the Thames Path will get you moved on. Camping here means a licensed site, and booking ahead is essential rather than advisable.

May, June and September are the best months. The first two give long evenings and dry ground before peak rates arrive; September holds the warmth with fewer people and lower prices. Several London sites now trade year-round, and winter camping is perfectly feasible given how light the frost is, though the short days make the trip in and out of the centre less appealing.