pass, opening or way by which a natural or artificial barrier can be crossed. The term pass is usually applied to a relatively narrow passage through a mountainous region. A pass, like an isthmus, may have great strategic and economic importance; the history of a nation has often been determined by its success or failure in defending a pass, and land trade routes must necessarily cross passes. In the Alps, Saint Bernard, Simplon, and Saint Gotthard are important; in the Caucasus, Daryal is traversed by a great military road; in Asia, Khyber Pass into India and the passes of the Himalayas, Karakorum, and other ranges are important.

Yellowhead Pass, 3,711 ft (1,131 m) high, in the Rocky Mts., on the boundary between Alta. and British Columbia, Canada, and W of Jasper, Alta. It is used by the Canadian National Railway.

White Pass, 2,888 ft (880 m) high, in the Coast Mts., on the Alaska-British Columbia border, NE of Skagway. A hazardous trail through the pass was made (1897) by prospectors going to the Klondike, as an alternate route to the Chilkoot Pass. Between 1898 and 1900 the White Pass and Yukon Railway was built from Skagway to White Horse, Yukon, to provide transportation from the Pacific tidewater to the Yukon valley. The railway suspended service in 1982.

Uspallata Pass, c.12,500 ft (3,810 m) high, over the Andes between Mendoza, Argentina, and Santiago, Chile. A trail—and later a rough road—for men and pack animals was used before the Transandine Railway (1910-82) was built. The Pan-American Highway now runs near the pass, through the Christ the Redeemer Tunnel. In 1817 José de San Martín sent part of his patriot army through the pass to fight the Spanish royalists in Chile. The Christ of the Andes statue stands in the pass. Mt. Aconcagua towers to the north. The pass is also known as Paso de la Cumbre [Summit Pass] and Paso Los Libertadores [Liberators Pass].

Three Pagodas Pass, mountain pass, alt. 925 ft (282 m), at the southern end of the Dawna Range, on the Myanmar-Thailand border. It has long been the chief route between SE Myanmar and the Chao Phraya valley of Thailand.

Stelvio Pass, alt. 9,048 ft (2,758 m), in the central Alps, N Italy, near the Swiss and Austrian borders. It is crossed by the highest road in the Alps, connecting the Valtellina with the upper Adige River valley. The road, extending c.30 mi (50 km) from Bormio to Trafoi, was begun in 1820 by the Austrians.

South Pass, broad, level valley (alt. c.7,550 ft/2,301 m), SW Wyo., cutting across the Rocky Mts. It was used by trappers and explorers before Jedediah Smith inaugurated its use as a route for settlers. An important unit of the Oregon Trail, it served for many years as a gateway for immigration to the west of the Rockies and was later a part of the pony express route.

Poncha Pass, 9,012 ft (2,747 m) high, central Colo., in the northern tip of the Sangre de Cristo Mts. One of the lowest mountain passes in Colorado, it was often used in the 19th cent. by Native Americans, overland immigrants, and mountain men. Poncha Pass is now crossed by a highway.

Killiecrankie, Pass of, wooded pass, Perth and Kinross, central Scotland, through which the river Garry flows, near Pitlochry. There Jacobite Highlanders defeated (1689) a large government force under Hugh MacKay, and the Jacobite leader, Viscount Dundee, was killed.

Khyber Pass, narrow, steep-sided pass, 28 mi (45 km) long, winding through the Safed Koh Mts., on the Pakistan-Afghanistan border; highest point is 3,500 ft (1,067 m). The routes through it link the cities of Peshawar, Pakistan, and Kabul, Afghanistan. For centuries a trade and invasion route from central Asia, the Khyber Pass was one of the principal approaches of the armies of Alexander the Great, Timur, Babur, Mahmud of Ghazna, and Nadir Shah in their invasions of India. The pass was also important in the Afghan Wars fought by the British in the 19th cent. The Khyber Pass is now traversed by an asphalt road and an old caravan route. A railroad (built 1920-25), which passes through 34 tunnels and over 92 bridges and culverts, runs to the Afghan border. Pakistan controls the entire pass.

Kasserine Pass, gap, 2 mi (3.2 km) wide, central Tunisia, in the Grand Dorsal chain (an extension of the Atlas Mts.). A key point in the Allied offensive in Tunisia in World War II, the pass was the scene of an Axis breakthrough (Feb. 20, 1943), but it was retaken with very heavy losses by U.S. forces on Feb. 25. See North Africa, campaigns in.

Grants Pass, city (1990 pop. 17,488), seat of Josephine co., SW Oreg., on the Rogue River, in a heavily forested area; inc. 1887. It has meat-processing and wood-products industries and is a trade center for the region's flower bulbs (especially gladioli), fruits, nuts, vegetables, and dairy products. The city is headquarters for Siskiyou National Forest and is the gateway to a nearby recreational area.

Eagle Pass, city (1990 pop. 20,651), seat of Maverick co., W Tex., a port of entry on the Rio Grande opposite Piedras Negras, Mexico; inc. 1918. Linked by highway with Mexico City, it is a tourist center and a shipping and processing point for cattle, wheat, pecans, and oats. Mineral processing (especially oil and gas) and international trade are also important, but drug smuggling has been a problem in recent years. The site of a U.S. army camp during the Mexican War, it was on an important route to California during the gold rush. Fort Duncan (1849) was a base for actions against Mexicans and Native Americans, including the 1855 burning of Piedras Negras; it also housed U.S. troops during the Villa revolution in Mexico just before World War I.

Chilkoot Pass, alt. c.3,500 ft (1,070 m), in the Coast Mts., on the British Columbia-Alaska line. The Chilkoot people long used it to pass between the Pacific coast and the Yukon River valley. Whites first traversed the pass in 1878, and after the Klondike gold strike (1896), it became a much-used route from Skagway, Alaska, to the interior.

Brünig Pass, 3,396 ft (1,035 m) high, ancient route between the Forest Cantons and the Bernese Alps, central Switzerland. It is crossed by a highway and a railroad.

Brenner Pass, Ital. Brennero, Alpine pass, 4,495 ft (1,370 m) high, connecting Innsbruck, Austria, with Bolzano, Italy. The lowest of the principal Alpine passes, it was an important Roman route through which many invasions of Italy were made. A long carriage road was built c.1772, and the railroad was completed in 1867. The pass became the border between Italy and Austria after World War I. During World War II, Hitler and Mussolini held three meetings there. Today the Brenner Highway, constructed in the early 1970s, is one of the major roads between Austria and Italy.

Bolan Pass or Bholan Pass, gap in the central Brahui Range, W Pakistan; c.60 mi (100 km) long, alt. 5,880 ft (1,792 m). A railroad and highway cross the pass en route to the Afghanistan frontier. Strategically located, traders, invaders, and nomadic tribes used it as a gateway to India.

Bholan Pass, Pakistan: see Bolan Pass.

Athabasca Pass, 5,736 ft (1,748 m) high, W Alta. and E British Columbia, Canada, leading from the headwaters of the Athabasca River across the Continental Divide to the Columbia River. It was discovered by David Thompson, a Canadian fur trader, or one of his agents c.1811, and for the next 50 years it was the chief route of the Hudson's Bay men on their journeys to and from the Columbia River country.

Pass in the Spīn Ghār (Safīd Kūh) Range on the border between Afghanistan and Pakistan. About 33 mi (53 km) long, it has historically been the gateway for invasions of the Indian subcontinent from the northwest; it was traversed by Persians, Greeks, Mughals, and Afghans from the north and by the British from the south. The Pashtun Afridi people of the Khyber area long resisted foreign control, but during the Second Anglo-Afghan War in 1879, the Khyber tribes came under British rule. It is now controlled by Pakistan.

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