South Gate, city (1990 pop. 86,284), Los Angeles co., S Calif., an industrial suburb of Los Angeles; inc. 1923. Among the city's manufactures are metal, electrical, paper, and rubber products; consumer goods; machinery; foods; chemicals; cutting tools; and furniture. The city's population increased significantly in the late 20th century.

Iron Gate, Rom. Porţile de Fier, Serbian Gvozdena Vrata, gorge of the Danube River, c.2 mi (3.2 km) long and c.550 ft (170 m) wide, on the Serbia-Romania border between Orşova and Drobeta-Turnu Severin. There the river narrows and swiftly flows through a gap between the Carpathian and Balkan mts. Iron Gate, formerly an obstacle to shipping, was cleared of rock obstructions in the 1860s; the Sip Canal (opened 1896) permits large river craft to get past the gorge. Iron Gate is the site of one of Europe's largest hydroelectric power dams. The joint Serbian-Montenegrin-Romanian project (opened 1971) improved river navigation by impounding a large lake and has a substantial electricity generating capacity.

Hell Gate, narrow channel of the East River, SE N.Y., between Wards Island and Astoria, Queens, New York City. Named Hellegat by the Dutch navigator Adriaen Block, who passed through it into Long Island Sound in 1614, it was dangerous to ships because of its strong tidal currents and rocks. Cleared of all obstacles, it allows oceangoing vessels to sail between New York harbor and Long Island Sound. It is crossed by the Triborough highway bridge and by the Hell Gate railroad bridge.

Golden Gate National Recreation Area, Calif.: see National Parks and Monuments (table).

Golden Gate Bridge, across the Golden Gate from San Francisco to Marin Co., W Calif.; built 1933-37. Its overall length is 9,266 ft (2,824 m); its main span across the strait, 4,200 ft (1,280 m), is one of the longest bridges in the world. Joseph B. Strauss was the chief engineer.

Golden Gate, strait, 4 mi (6.4 km) long and 1 to 2 mi (1.6-3.2 km) wide, linking San Francisco Bay with the Pacific Ocean. It was discovered in 1579 by the English explorer Sir Francis Drake. Known as the Golden Gate before the California gold rush, its name became popular during this period because of its mineral connotation. The strait is the drowned mouth of the united Sacramento and San Joaquin rivers and forms an excellent channel, c.400 ft (120 m) deep, into San Francisco Bay. Adorning the strait is the famous Golden Gate Bridge.

Suspension bridge spanning the Golden Gate, San Francisco. From its completion in 1937 until the completion of New York's Verrazano-Narrows Bridge in 1964, it had the longest main span in the world, 4,200 ft (1,280 m). It remains incomparable in its magnificence. Its construction, supervised by Joseph B. Strauss (1870–1938), involved many difficulties: rapidly running tides, frequent storms and fogs, and the problem of blasting rock under deep water to plant earthquake-resistant foundations.

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