RIDGE encyclopedia topics

Wheat Ridge, city (1990 pop. 29,419), Jefferson co., N central Colo., a suburb of Denver; inc. 1969. Chiefly residential, Wheat Ridge is the site of an annual carnation festival.

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Salair Ridge

Salair Ridge, range, c.200 mi (320 km) long, E Siberian Russia. Extending along the northern border of the Altai Territory, it rises to more than 2,000 ft (610 m) and forms the western edge of the Kuznetsk Basin; to the south it merges with the Kuznetsk Alatau range. The Salair Ridge has iron, lead, silver, and zinc deposits.

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Ridge, Tom

Ridge, Tom (Thomas Joseph Ridge), 1945-, U.S. politician and government official, first secretary of the Dept. of Homeland Security (2003-5), b. Munhall, Pa. A graduate of Harvard (1967) and the Dickinson School of Law (1972) who served (1968-70) in the infantry in Vietnam, Ridge worked in private law practice and became active in the Republican party. In 1982 he was elected to the House of Representatives from Pennsylvania and served six terms. Elected governor of his home state in 1994, he was in his second term when President George W. Bush asked him to head the Office of Homeland Security in the aftermath of the Sept. 11, 2001, terrorist attacks (see Pentagon, the; World Trade Center). Chosen to head the newly established Dept. of Homeland Security (DHS) in 2003, Ridge oversaw the integration of the 22 agencies that were consolidated and reorganized in the DHS.

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Pleasure Ridge Park

Pleasure Ridge Park, uninc. town (1990 pop. 25,131), Jefferson co., N Ky. It is a residential suburb of Louisville.

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Pea Ridge National Military Park

Pea Ridge National Military Park: see National Parks and Monuments (table).

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Pea Ridge

Pea Ridge, chain of hills, NW Ark., where the Civil War battle of Pea Ridge (or Elkhorn Tavern) was fought Mar. 6-8, 1862. Earl Van Dorn, leading a large Confederate command, which included Sterling Price's retreating Missouri forces and Ben McCulloch's army, attacked the strongly entrenched Union army under Samuel Ryan Curtis. The Confederate wings, becoming separated, were crushed on successive days. Pea Ridge was the first decisive victory won by the Union army W of the Mississippi; not until Price's raid (1864) did the Confederates again try to carry the war to Missouri in force.

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Park Ridge

Park Ridge, city (1990 pop. 36,175), Cook co., NE Ill., a suburb adjacent to Chicago, on the Des Plaines River; inc. 1873. It is chiefly residential. Several national and international corporations have their headquarters in Park Ridge. Nearby is O'Hare International Airport.

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Oak Ridge

Oak Ridge, city (1990 pop. 27,310), Anderson and Roane counties, E Tenn., on Black Oak Ridge and the Clinch River; founded by the U.S. government 1942, inc. as an independent city 1959. For years Oak Ridge was used by the federal government to pursue activities in the fields of atomic energy and nuclear physics. The site was chosen (1942) for what was called the Clinton Engineer Works, and the city was built to house the workers who developed the uranium-235 and plutonium-239 for the atomic bomb. The community's existence was kept secret from most of the country until the summer of 1945. The project was under the control of the Atomic Energy Commission, but the city has since (1955-59) been turned over to its residents. The former Clinton National Laboratory for nuclear research became (1948) the Oak Ridge National Laboratory. In the 1990s the federal government began decontaminating and leasing much of the complex to private industry, and one section was renamed the East Tennessee Technology Park. The Oak Ridge Associated Universities, a consortium of many educational institutions, manages the Oak Ridge Institute for Science and Education. Tourist attractions include the American Museum of Atomic Energy, a nearby nuclear graphite reactor, and an arboretum.

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Missionary Ridge

Missionary Ridge: see Chattanooga campaign.

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Mid-Atlantic Ridge

Mid-Atlantic Ridge: see Atlantic Ocean.

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East Ridge

East Ridge, town (1990 pop. 21,101), Hamilton co., SE Tenn., a suburb of Chattanooga, near the Ga. border; inc. 1921. It is chiefly residential.

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Cutler Ridge

Cutler Ridge, uninc. town (1990 pop. 21,268), Miami-Dade co., SE Fla., a growing residential and commercial suburb of Miami.

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Blue Ridge

Blue Ridge, eastern range of the Appalachian Mts., extending south from S Pa. to N Ga.; highest mountains in the E United States. Mt. Mitchell, 6,684 ft (2,037 m) high, is the tallest peak. Beginning with a narrow ridge in the north, c.10 mi (16 km) wide, the range broadens toward the south, reaching a maximum width of 70 mi (113 km) in North Carolina. Receiving much rain, the region is heavily forested; wood is the area's chief resource. The Blue Ridge was a barrier to the pioneers' westward movement. Numerous gaps cross the ridge; the gap at Harpers Ferry, W.Va., was an important railroad traverse. Most of the people of the Blue Ridge live on small farms in sheltered valleys and retain traditional lifestyles and speech. Principal economic activities there include livestock raising, farming, tobacco growing, and lumber production. Commercial apple orchards are found in Virginia, Maryland, and Pennsylvania. The Blue Ridge is a major East Coast recreation area noted for its resorts and scenery. The Appalachian Trail winds atop the range. Skyline Drive, Va., following the crest of the Blue Ridge in Shenandoah National Park, has many roadside lookouts. The Blue Ridge Parkway (see National Parks and Monuments, table), designed especially for motor recreation, links the Shenandoah and Great Smoky Mts. national parks.

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oceanic ridge

Continuous, submarine mountain chain extending approximately 50,000 mi (80,000 km) through all the world's oceans, separating them into distinct basins. The main ridge extends down the middle of the Atlantic Ocean, passes between Africa and Antarctica, turns north to the Indian Ocean, then continues between Australia, New Zealand, and Antarctica and across the Pacific basin to the mouth of the Gulf of California. Lateral ridges extend from islands on the axis of the oceanic ridge to coasts of adjacent continents. The oceanic ridge system is the largest feature of the Earth's surface after the continents and the ocean basins themselves; it is explained by the theory of plate tectonics as a boundary between diverging plates where molten rock is brought up from deep beneath the Earth's crust. Seealso subduction zone.

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Encyclopedia Britannica, 2008. Encyclopedia Britannica Online.

Mid-Atlantic Ridge

Submarine ridge lying along the floor of the central Atlantic Ocean. It is a long mountain chain running about 10,000 mi (16,000 km) in a general but curving north-south direction from the Arctic Ocean to the southern tip of Africa. The mountains sometimes reach above sea level, forming such islands or island groups as Ascension, the Azores, St. Helena, and Tristan da Cunha.

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Encyclopedia Britannica, 2008. Encyclopedia Britannica Online.

Blue Ridge

or Blue Ridge Mountains

Section of the Appalachian Mountains, eastern U.S. The range extends southward from Carlisle, Pa., through parts of Maryland, Virginia, North Carolina, and South Carolina to Mt. Oglethorpe in Georgia. The highest peaks are in the Black Mountains of North Carolina; the average elevation is 2,000–4,000 ft (600–1,200 m). The scenic Blue Ridge Parkway, established in 1936 and administered by the National Park Service, runs 469 mi (755 km) along the crest.

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Encyclopedia Britannica, 2008. Encyclopedia Britannica Online.