Impossible expectations are often applied. Travellers expect not only pleasure from this vexing, magnificent country but transcendence as well. From the moment the plane screechesdown at Delhi's Indira Gandhi International Airport, India conspires forcibly to rearrange your senses - starting with the capital.
Most flights from Europe arrive in Delhi around 2am, when your defences are down. The immigration queues are endless, and you are given little slips of paper which you must not lose; otherwise, you are subjected to a public haranguing by bureaucrats dressed up like admirals.
At the airport bank, your travellers cheques are transformed into a stack of dirty rupee notes that are stapled together. There is a knack to twisting out these staples, but it takes months to learn and you will sacrifice too many rupee notes in the process. The best advice is to place all your belongings on the floor and perform surgery on the banknotes with your Swiss Army knife. Get used to this ritual, for you'll be performing it again, in stations, tea stalls and bazaars, often with crowds pressing in, yelling advice.
The next ordeal is arranging transportation into Delhi. After you've prized free the notes you will be surrounded by many men who want to liberate some of your rupees by offering "cheap" transportation into the city, 15 miles away. Get used to this, too: these taxi-wallahs break you in for the more persistent and crafty hustlers who will dog you, like marathon relay teams, up and down India. Don't take it personally; it's a game for them, and they'll expect you to play along.
Once you step outside the terminal, the air has a distinctive, loamish smell of cowdung fires, cheap beedi cigarettes and earth that's been ploughed for a millennium. Hundreds of sleeping bodies lie on the pavement; they are labourers waiting for their next morning's flight to the Gulf, but their presence gives an impression that the airport is the high water mark of some catastrophe that has washed up a flood of refugees.
It was into this darkness that I first landed in India with my family. My young son was asleep, slumped on to the luggage cart. I turned around and saw that a man who was wearing nothing but a coat of ash and a stiff, monkey-like tail was bent over my son, stroking his face with incandescent curiosity. My son never woke, and the monkey-man scampered off. I later learnt he was a follower of Hanuman, the monkey-god, and that the monkey- man's attention to my child was considered auspicious. I did not think so at the time.
Many travellers spend as short a stay as possible in Delhi, trying to gather their bearings. They scarcely bother to see the city, which lays convincing claim to being one of the oldest in the world, going back at least 1,000 years. You see the travellers in the cheap cafes of Paharganj with their guide books out, plotting escape routes to the Rajasthan desert, Ladakh or Goa.
However, Delhi is worth a linger. It is like exploring a maze plotted through space and time, in which one turn, say, down the lanes of Nizamuddin with its Muslim butchers, booksellers and vendors of rose and antimony, can land you back in the 13th century. Another turn and you see the chrome and glass skyscrapers of Connaught Place jutting above the ramparts of Purana Qila, the sandstone fort built by Moghuls. Behind the tyre shops in Kailash hills, you can find a third-century pillar carved with the Buddhist edicts of emperor Ashoka; inside the gardens surrounding Humayun's tomb, where green parakeets dart between the banyan trees, it is easy to forget the roar of a city trying desperately to pull itself into the 21st century.
When New Delhi was named the imperial capital in 1911, no attempt was made to integrate the old and new cities. The architect, Sir Edwin Lutyens, just plunked down his boulevards, his Anglo-Moghul edifices, his spoked roads and roundabouts with colonial hauteur.
This jarring dislocation gives the city an edginess, a schizophrenia. My wall map has green belts marked off as "fairly dense jungle", and it also has a vast blank space where the 17th-century walled-in city of Old Delhi stands, as if that were also a jungle - of human habitation - one so dense that it has defied penetration by cartographers. Indians are understandably proud of their capital; the panoramic sweep from India Gate to Rashtrapati Bhavan is as monumental as the nation itself. But a tailor or sweet maker who has spent his life confined in the warrens of Old Delhi must experience an acute fear of open spaces if he ever ventures into New Delhi.
Old Delhi once thronged with poets, artisans and jewellers who catered to the whims of the Moghul court. As the empire weakened, invaders pillaged Delhi. The bejewelled Peacock Throne was carted off to Persia, and artisans and architects were also dragged off to build nouveau-riche palaces and mosques. Since the British deposed the last Moghul emperor after the 1857 Mutiny, Old Delhi is more geared towards commerce than poetry. The noblemen's exquisite havelis, or city palaces, are now sub-divided a hundred times over. Three generations of a family live in each cubicle, taking turns on a single Singer sewing machine affixing labels to fancy shirts. Some of the last descendants of the Moghul emperors are now reduced to running a small travel agency inside Old Delhi.
Delhi and its people still carry the scars of the 1947 Partition, when hundreds of thousands of Hindu and Sikh refugees fled here from the newly created Muslim state of Pakistan. The sense of uprootedness has never left these immigrants. They have made Delhi a restless city.
In Bombay, you ask someone his profession. In Delhi the question that answers all others is: where do you live? During partition, land in New Delhi was parcelled out according to where the refugees had come from or what government jobs they held. So if someone tells you he's from Chittarangan Park in south Delhi, chances are he's a Bengali (from what first became East Pakistan and is now Bangladesh), a civil servant, devoted to the demon-slaying goddess Durga, and he and his family will probably be having fish for dinner. The Sikh taxi driver probably lives in Karol Bagh, a bustling west Delhi neighbourhood where they wolf down tandoori from places like "Pick a Chick". And everyone, no matter what neighbourhood they live in, likes to pretend they are Someone Important in Government. A favourite accessory, on even the most battered Ambassador cars, is a furled flag for the bonnet. The idea is that it wards off traffic cops.
This is not to say that all India is encompassed in Delhi, or that a week-long trip to the capital, with maybe a day-trip to the Taj Mahal, will suffice. This nation, with its 900 million people, 18 languages and 1,652 dialects, can never be squeezed into one city. Delhi's ethos and manners are distinctly northern-Indian, pushy and brash, but for most travellersthe city acts as a useful decompression chamber before taking the real plunge into India.
How to get there
Numerous agents sell discounted tickets, particularly to Delhi and Bombay. Welcome Travel (0171-439 3627) has non-stop flights on Air India between London and Delhi for pounds 475. For a much cheaper trip, Turkmenistan Airlines (0171-355 1969) operates weekly from both Birmingham and Heathrow to Delhi via Ashkhabad for pounds 270.
How to get in
British visitors need a visa, obtainable from the High Commissioner for India, India House, Aldwych, London WC2B 4NA (0171-836 8484).
William Dalrymple, author of the award-winning travel book City of Djinns, is leading a tour of northern India based upon the book. It takes place next 15-29 March, and visits Delhi, Jaipur, Agra and the Taj Mahal, and costs pounds 1,995. The organiser, Steppes East (01285 810267) also features a journey to southern India led by the writer Louise Nicholson from 8- 26 March.
"Standards of safety and comfort in India and Pakistan tend to be lower than those pertaining in the UK. Our aim is to provide you with an insight into the realities of everyday life in the country visited, rather than to insulate your from them." So warns Butterfield's Indian Railway Tours (01262 470230). The company attaches its own carriage to scheduled trains, and thus provides the chance to travel through India by train from top to toe. A trip from Delhi in the north to Kochi in the south costs pounds 845, plus the cost of international travel.
The Travellers' Club, meanwhile offers tours with a flavour of "real India" - visits to farms, homes, small villages. For details call 01243 773597.
Charter flights planned to start this winter between Gatwick and Agra, the airport adjacent to the Taj Mahal, have been withdrawn, but charters elsewhere in India are widely available. Somak Holidays (0181-423 3000) is offering a fortnight at the Osborne Resort in Goa for pounds 369 including B&B, departing 1 December.
The British Museum Traveller (0171-323 8895) has two tours early next year: in January, 16 days among traces of the Mughal dynasty in India and Pakistan (pounds 1,990), and in February 17 days around the temple cities of southern India (pounds 1,995). Each trip is led by an expert in the field.
What to read
Few areas of publishing have expanded as rapidly as the growth in guidebooks to India. This month Cadogan Guides enters the fray with books on South India (pounds 14.99) and Goa (pounds 8.99). They join the Rough Guide to India (pounds 13.99) and the 1996 India Handbook (Trade and Travel, pounds 16.95); the sixth edition of India: a Travel Survival Kit, is published in January by Lonely Planet, at pounds 14.95.
Who to ask
Government of India Tourist Office, 7 Cork St, London W1X 1PB (0171-437 3677).
India comes to the South Bank in London on 3 December, when the Akshaya Dance Theatre stages The Secret of Life, which the company describes as "a powerful drama incorporating passion, lust, greed, murder and betrayal". Tickets are available on 0171-960 4242.