highway: see road.

Trans-Canada Highway, c.4,800 mi (7,700 km) long, S Canada; dedicated 1962; completed 1970. The world's longest national highway, it traverses North America from St. John's, N.L., to Victoria, British Columbia. Ferry routes form vital links at the eastern and western ends of the highway. The Alaska Highway joins the Trans-Canada Highway at Calgary, Alta.

Trans-Amazon Highway, road, c.3,000 mi (4,830 km) long, traversing N central Brazil. The highway, stretching from the Atlantic coast to the Peruvian border, is an important factor in the economic development of the Amazon region.

Pan-American Highway, system of roads, c.16,000 mi (25,750 km) long, linking the nations of the Western Hemisphere. It was suggested at the Fifth International Conference of American States (1923) and supported and financed by the United States during the 1940s and 1950s. Gaps are in Panama (Darién Gap) and N Colombia, in the section called the Inter-American Highway. The route from Yaviza (Panama) to Colombia is surveyed but not constructed. The section between the United States and the Panama Canal is popular with tourists driving to Mexico. Climatic zones along the highway vary from lush jungle to cold mountain passes nearly 15,000 ft (4,572 m) high. The scenery is often spectacular, and the highway crosses many picturesque localities. The system is far from uniform; some stretches are passable only during the dry season, and in several regions driving is occasionally hazardous. In the late 1960s, much of the highway was improved.

Inter-American Highway, c.3,400 mi (5,470 km) long, section of the Pan-American Highway system from Nuevo Laredo, Mexico, to Panama City, Panama. Much of the highway prior to 1941 had been built by the countries concerned, but wartime necessity led the United States to appropriate funds to assist completion. Later work was done by each nation on its own. The highway includes alternate routes and makes use of existing local roads. It is virtually complete, and many sections have been upgraded and paved.

Alaska Highway, all-weather road, 1,523 mi (2,451 km) long, extending NW from Dawson Creek, British Columbia, to Fairbanks, Alaska. An extension of an existing Canadian road between Dawson Creek and Edmonton, Alta., the Alaska Highway was constructed (Mar.-Sept., 1942) by U.S. troops as a supply route to military forces in Alaska during World War II. It was a significant engineering feat because of the difficulties of terrain and weather. In the last stretch to Fairbanks the road used the previously built Richardson Highway. The Haines Cutoff connects the Alaska Highway with the Alaska panhandle. In 1946 control of the Canadian part of the road was transferred to Canada. In 1947 the entire highway was opened to unrestricted travel; it is one of the best routes to Alaska. The highway is open throughout the year, and there are roadside facilities along its length. It was formerly known as the Alaskan International Highway and the Alcan Highway.

World's longest national road, extending east-west for 4,860 mi (7,821 km) between Victoria, British Columbia, and St. John's, Newfoundland. Completed in 1965, it links many major Canadian cities and provides access to important national and provincial parks.

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International highway system connecting North and South America. Conceived in 1923 as a single route, the road grew to include a number of designated highways in participating countries, including the Inter-American Highway from Nuevo Laredo, Mex., to Panama City, Pan. The whole system, extending from Alaska and Canada to Chile, Argentina, and Brazil, totals nearly 30,000 mi (48,000 km). Only some 240 miles (400 km) in the Panama-Colombia border area remain uncompleted.

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formerly Alcan Highway

Road through the Yukon, connecting Dawson Creek, British Columbia, with Fairbanks, Alaska, a distance of 1,523 mi (2,451 km). It was constructed by U.S. Army engineers in 1942 as an emergency war measure to provide an overland military supply route to Alaska. It is a scenic route now open year-round.

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