Tertiary sector is the field where the United States are more advanced.
The 72,1% of GDP comes from tertiary and 73.3% of workers is employed in tertiary sector.

Great importance is given to the 300,000 km of railway network, used more than anything else for the transport of goods and is integrated with a super-efficient road network; the rail and road network cover the whole territory helping the transport of goods and travel.

Despite the attack of 11 September, air transport, with its 16,000 airports, is one of the favorites by Americans.
We can say that in America the plane is used as in Italy is used the train.

Also the sea transport is extremely developed.
The modern transport network has favored the birth of commercial activities linked to it as insurance, freight forwarders and service areas.

Other service sectors very efficient are private schools, which offer, in addition to a high degree of teaching, safety: infact as the frequency of shooting in public schools, we must pass under the metal detector placed to entry.

Washington D.C. is the capital city of the United States, located between Virginia and Maryland on the north of the Potomac River.

Its name is given in honor of George Washington, the first president of the United States of America and the city is home to all three branches of the federal government, as well as the White House, the Supreme Court and the Capitol Building.
More than 500,000 people live in Washington, D.C.

Washington D.C. is a city with strong contrasts: on the one hand boasts magnificent monuments, buildings and wide boulevards and from the other poor neighborhoods inhabited mainly by immigrants and the needy, that surround the city.

New York city is the largest city in America, the most populous (8.5 million inhabitants) and is one of the most important economic and cultural centers of the world (recognized as a global city).

New York is nicknamed "the big apple" and "the city that never sleeps."

It is divided into five districts (boroughs): Manhattan, The Bronx, Queens, Brooklyn and Staten Island.

The home of Hollywood and the film industry, full of palms city, offers mountains, beaches, sunsets and everything else tourists are hoping to find in California.

Los Angeles is now the largest and most populous city in California and the second of all the United States of America.

San Francisco is a popular destination for many international tourists, and is known for its cool summer fog, for its steep hills, its architecture, which combines Victorian and modern architecture, for its famous landmarks, including the Golden Gate Bridge, for its tram and Chinatown.

It is a mock city, unreal, made of lights, dreams and hopes, that came out of nowhere in the middle of the Nevada desert, visited by millions of tourists vacation.

Nicknamed Sin City, Las Vegas attracts over 30 million visitors with a passion of gambling.

The Grand Canyon is a big gorge carved by the Colorado River in the U.S. state of Arizona in North America.

The Grand Canyon is 277 miles (446 km) long and attract about 5 million visitors per year.

The legendary vast area of marshland and coastal mangrove is one of the wonders of the world that has been declared a World Heritage Site, International Biosphere Reserve and Wetland of International Importance.

The alligators, Lincoln logs, reign in the swamp, particularly along the 25-mile Loop Road that leads off the main highway into the deep Everglades.

Niagara Falls is the collective name for three waterfalls that straddle the international border between Canada　and the United States.
The waterfalls are the Horseshoe Falls, the American Falls and the Bridal Veil Falls.

In this below-sea-level basin, steady drought and record summer heat make Death Valley a land of extremes.
Yet, each extreme has a striking contrast. Towering peaks are frosted with winter snow. Rare rainstorms bring vast fields of wildflowers. Lush oases harbor tiny fish and refuge for wildlife and humans. Despite its morbid name, a great diversity of life survives in Death Valley.