Sightseeing in the USA is a lifelong pursuit, such is the vast scale and variety of the attractions on offer. Indeed the USA is far more than a single country, as each state and region has its own character, geography and unique, world-class sights.

Three-quarters of all foreign tourists spend time in California, Florida and New York, while the country's five most visited cities by foreign tourists are in these three states. In between east coast California's beaches, movie glitz and sunny weather and west coast New York's urban thrills and iconic sights is a country of stunning diversity: the Creole culture of Louisiana, the wide-open plains of the great mid-West, epic skiing around the Rocky Mountains, the magnificence of the Grand Canyon and astounding lights of nearby Las Vegas. Off shore Hawaii is a place of irresistible beauty too, and Alaska offers a unique wilderness to explore.

Given all there is to see and do, and the vast distances between them, you'll need to plan your trip carefully and concentrate on a few areas. Be aware that winters (November to February) in the east coast get very cold with plenty of snow, while beaches can get uncomfortably hot over peak summer months of July and August. Also look out for big national events like Spring Break (March), Fourth of July, and Thanksgiving (fourth Thursday in November) when transport and accommodation get very busy.

In such a large country, filled with so many diverse groups, business practices may differ according to each state, however rarely to any large degree. The East Coast is traditionally more formal than the West Coast, however in states such as California dress code and conservative appearance are as common as they would be in New York. Punctuality is important throughout the country and it is considered rude to be late for a meeting. Gift-giving is uncommon as it may be construed as bribery. Appropriate titles (Mr, Mrs, Ms) are used upon introduction and until otherwise stated. Americans favour politeness and greetings of 'Hello' and 'How are you?' are often expressed with sincerity. Business hours may vary in each state, but an 8am start and 5pm finish Monday to Friday is the most common with an hour over lunch.

Status and age are not necessarily indicative of seniority, nor do they carry much weight in themselves. Those doing business in the States should be mindful of this fact; never make assumptions about someone's position or rank. Best practice is to be respectful to all parties. That said, the States upholds a hierarchal business structure, in which "the boss" is the ultimate decision-maker. Senior leaders have the power of the last word, and can go against the grain just as easily as they can follow popular opinion. Concentrate on winning over this individual, even if the greater group seems unsupportive. Americans value a direct style of communication. In this fast-paced, consumer culture "time is money", and small-talk is viewed as unnecessary and wasteful. Get to the point quickly, speak about issues in a frank and open manner, and don't take offence if someone questions or challenges you outright.

The United States of America covers a large region, stretching from east to west across six time zones and therefore it is no surprise that the country has a varied climate, ranging from arctic regions to deserts. California, on the west coast of the US, has a pleasant, Mediterranean climate, and the Pacific Northwest Coast has more of a maritime climate, with cooler summers and mild winters, influenced by westerly winds. The central part of the US has extreme temperature variations and a continental climate - with cold winters and hot summers (with tornadoes). The eastern central US tends to be more humid, while the western central US is semiarid. The east side of the country has a continental climate caused by air masses moving from west to east, with hot summers and a prevalence of tornadoes in the Mississippi River area. Florida has the warmest winters on the eastern seaboard. It is recommended that travellers research the climate in the specific state they wish to visit when choosing when to travel.

The international country dialling code for the United States is +1. The outgoing code is 011, followed by the relevant country code (e.g. 01144 for the United Kingdom). The US has numerous area/city codes, which must be dialled before the local number required (e.g. New York Manhattan, 212, and Washington DC, 202). Mobile networks cover most of the country, including all urban areas, however unless you have a tri-band phone it is likely your cellular phone from home will not work in the United States. The largest GSM networks are T-mobile and Cingular. Internet cafes are prevalent in most towns and cities.

Laws vary from state to state, including speed limit, fines and punishment. The age at which you may legally buy and consume alcohol is 21 years.

Travellers to the United States who are returning residents of the country do not have to pay duty on articles purchased abroad to the value of $800 provided their stay was longer than 48 hours and their duty-free allowance was not used in the 30-day period prior. For passengers arriving from Samoa, Guam and the U.S. Virgin Islands, a duty-free allowance of $1, 200 is allowed. The following items are included in this: 50 cigarettes and 10 cigars and 150 milliliters (5 fl. oz.) of alcoholic beverages or 150 milliliters (5 fl. oz.) of perfume containing alcohol. Restrictions may apply to goods from Cuba, Iran, North Korea, Burma (Myanmar), Angola, Liberia and Sudan. It is prohibited to import Cuban cigars from any country. Travellers to the United States who are non-residents do not have to pay duty on the following items: 50 cigars or 200 cigarettes and gifts to the value of $100 provided their stay in the USA is not less than 72 hours and that the allowance has not been used in the preceding six-month period. Prohibited items for residents and non-residents include: meat or meat products, poultry, narcotics, absinthe, plants, seeds, vegetables, fruits, soil, live insects and other living plants or animal pests. Fish is prohibited unless it carries disease-free certification. Wildlife and animals or their by-products carry restrictions. Dairy products and eggs from specified countries are not allowed. Firearms and ammunition are not allowed without the necessary license and permit.

120 volts, 60Hz. Plugs are mainly the type with two flat pins, though three-pin plugs are also widely used. European appliances without dual-voltage capabilities will require an adapter, which can be purchased in most major departure airports.

There are no specific health risks associated with travel within the USA. Medical facilities are excellent, but expensive. Only emergencies are treated without prior payment and treatment can be refused without evidence of insurance or proof of funds. Good medical insurance is essential.

English is the most common language but Spanish is often spoken in south-western states.

The US Dollar (USD) is the unit of currency and is divided into 100 cents. Only major banks exchange foreign currency. ATMs are widespread and credit cards and travellers cheques are widely accepted. Travellers cheques should be taken in US Dollars to avoid hassles. Banking hours are Monday to Friday 9am to 3pm.

Visitors entering the country under the Visa Waiver Programme (VWP) must have a machine-readable passport (MRP) that has a bar code on the photo page. From 26 October 2006 eligible travellers under the VWP must include biometrics in their machine-readable passports if they wish to enter the country without a visa, containing unique personal data such as fingerprints or iris details. All new passports issued on or after 26 October 2005 must contain a digital photo image in order to travel visa-free. Due to new security measures, all visitors to the USA will have a photograph and two fingerprints taken by an inkless scanner on arrival, including those travelling visa-free under the Visa Waiver Programme. As part of the Western Hemisphere Travel Initiative (WHTI), all travellers travelling between the United States and Canada, Mexico, Bermuda, and the Caribbean region are required to present a passport or other valid travel document to enter or re-enter the United States. If departing from the USA a valid passport will be required by immigration authorities. A new security regulation, in force from 2009, means that all visitors who do not need a visa under the US visa waiver programme will need to register online three days before travel. This will allow the US government to screen all visitors before travel. The new programme will be mandatory for all visa-free travel from 12 January 2009. For more information on visa visit: http://travel.state.gov/visa/visa_1750.html. It is highly recommended that passports have at least six months validity remaining after your intended date of departure from your travel destination. Immigration officials often apply different rules to those stated by travel agents and official sources.

Travel within the United States is generally trouble-free, however travellers should be aware that the US shares with the rest of the world an increased threat from terrorist incidents. Security has been heightened particularly at airports. Restrictions on hand luggage apply and travellers are advised to check on the latest situation with airlines in advance. Travellers should also be alert to the dangers of car and street crime in cities and should use common sense and take basic precautions. Hurricanes are common between June and November, putting the southern USA, including the Gulf Coast and the eastern US, at risk. There is a risk of wildfires in many dry areas in the US, particularly on the West Coast from March to November.

A 15% tip is expected by taxi drivers, bartenders, hairdressers and waiters, but don't tip in fast-food or self-service restaurants. In expensive restaurants or for large parties tip 20% of the bill. It is normal to tip staff staff such as valets and porters in hotels; this is discretionary although a minimum of $5 is expected. Most services are customarily tipped if the service is good.