TRANSPORTATIONAirlines service 817 cities throughout the country. A flight from New York to San Francisco takes five-and-a-half hours. Train service is also available: The most frequent service is between Washington, D.C., New York and Boston in the East; St. Louis, Chicago and Milwaukee in the Midwest; and San Diego, Los Angeles and San Francisco in the West. A coast-to-coast trip by train takes three days. The major means of intercity transportation is by automobile. Motorists can travel over an interstate highway system of 88,641 kilometers, which feeds into another 6,365,590 kilometers of roads and highways connecting virtually every city and town in the United States. A trip by automobile from coast to coast takes five to six days.
The development of transportation facilities was of crucial importance in the growth of the United States. The first routes of travel were natural waterways; the earliest overland routes were rough trails suitable for travel on foot or horseback. No surfaced roads existed until the 1790s. Many canals were constructed between the late 18th century and 1850 to link navigable rivers and lakes in the eastern United States and in the Great Lakes region. Steam railroads began to appear in the East in the 1820s. The first transcontinental railroad was constructed between 1862 and 1869 by the Union Pacific and Central Pacific companies, both of which received large subsidies from the federal government. Transcontinental railroads were the chief means of transportation used by European settlers who populated the West in the latter part of the 19th century and were also of utmost importance for moving goods from one part of the country to another. The railroads continued to expand until 1917, when the length of operated track reached a peak of about 407,000 km (about 253,000 mi). Thereafter, motor transport became a serious competitor of the railroads both for passengers and freight.
Air transport began to compete with other modes of transport in the United States after World War I. The first commercial flights in the United States were made in 1918 and carried mail. Passenger service began to gain importance in the late 1920s, but not until the advent of commercial jet craft after World War II did air transport become a leading mode of travel.
In terms of weight of goods multiplied by the distance transported, railroads in the 1990s carried the greatest share of the nation’s freight - 38 percent. Trucks carried 28 percent of goods, and oil pipelines conveyed 18 percent. Some 15 percent was shipped on inland waterways. Although the freight handled by airlines amounted to only 0.4 percent of the total, much of the cargo consisted of high-priority or high-value items.
In terms of the number of passengers multiplied by distance traveled, private automobiles accounted for about 81 percent of the total passenger traffic carried by the various modes of transportation. Airlines were the second leading mover of people, carrying 17 percent of the passenger traffic. Buses were responsible for 1 percent, and railroads carried 0.7 percent of passenger traffic.
Date: 2015-01-02; view: 1004
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