India shares common borders with China, Bhutan and Nepal to the north, Pakistan to the north-west, and Burma to the north east. To the east, almost surrounded by India, is Bangladesh. Near India's southern tip, across the Palk Strait, is Sri Lanka.
The country has 28 states which vary greatly in size, population and development. Each has its own government. There are also seven Union Territories with their Lieutenant Governors or Administrators.
The official language is Hindi, written in the Devanagari script. It is spoken by close to a third of the population as a first language. English is an 'associated language'. In addition there are 18 official state languages.
India has benefited greatly from the 'global economy' and the IT revolution and besides its traditional heavy industries, is now a major player in IT and software development, and call centre outsourcing. Even so 350m people remain in poverty.
India's largest cities are Mumbai (formerly Bombay), Delhi, Kolkata (formerly Calcutta), Chennai (formerly Madras), Bangalore, and Hyderabad.
The Foreign Office warns that there has been continued violence in the Kashmir Valley between armed groups seeking secession from India and against all travel to or through rural areas of Jammu and Kashmir (other than Ladakh), and all but essential air travel to Srinagar. It says there is a high level of conflict and terrorist violence in Jammu and Kashmir (excluding Ladakh). 'Jammu City is somewhat safer but attacks still occur'.
It also advises against all travel in the immediate vicinity of the border with Pakistan other than travel across the international border at Wagah, and against all but essential travel to Imphal (by air) and against all travel in the rest of Manipur and Tripura. 'Kidnapping, banditry and insurgency are rife throughout the north eastern region, particularly in Assam'.
Even in Mumbai British Nationals are advised to take care and avoid demonstrations.
'There is a high threat of terrorism throughout India', says the Foreign Office. 'Attacks have targeted public places, including places of worship. They could also target places frequented by expatriates and foreign travellers'.
However, 'over 600,000 British tourists visit India every year' and most are trouble free.
Between the months of December and April, flights leaving India become very full. Passengers may find themselves 'bumped off' flights even if they have confirmed seats. All international departures must therefore be re-confirmed at least 72 hours before departure.
The Foreign Office warns that penalties for possession of drugs can be severe. The penalties paedophile offences are also severe. And visitors to India should also be aware that Indian family law is very different from UK law and particular caution is needed when, for example, child custody becomes an issue.
There are health risks with seasonal outbreaks of some illnesses. Local medical facilities are 'not comparable to those in the UK, especially in more remote areas', says the Foreign Office. 'However, in the major cities private medical care is available, but is expensive'.
Travellers to India must obtain a visa before travelling. Foreign nationals arriving in India on long term multiple entry visas are required to register with the nearest Foreigners Regional Registration Officer within 14 days of arrival.
Overstayers are fined and may be prosecuted or detained and later deported. They may also need to appear in person at the Ministry of Home Affairs in Delhi.