The development of the modern American West dates from the midnineteenth century, when waves of frontiersmen, confronting what seemed a Great American Desert at the 98th meridian, leapfrogged across half a continent to the Pacific coast in response to the electrifying news of gold in California. From there, the newcomers quickly spread into other resource-rich areas of the region before gradually moving into the vast interior, where they joined with migrants from the East, Europe, and elsewhere to settle the intermountain plateaus and Great Plains. By 1890, there was no longer a discernible frontier line, and the stage was set for the phenomenal growth of the twentieth-century West. During the last century, the 17 contiguous western states and Alaska have moved from backwater status to world leaders in the development of large-scale mechanized agriculture and scientific stockraising, mineral extraction technologies, aerospace and electronic industries, massive multipurpose public works projects, banking, motion picture and television industries, and tourism. Growth in the American West, although uneven over the last century and a half, has been spectacular nearly everywhere. The greatest and most cosmopolitan population development has occurred in the urbanized areas along the Pacific coast and in the Sun Belt cities of the Southwest. By the mid-1980s, the West had some 70 million residents, raising it to coequal status with the nation's other regions. At the same time, the West, while very urban, remained the most rural U.S. region, with 747 million acres (one-third of the nation's land area) available for agriculture and an additional 690 million acres in government ownership as national parks, forests, monuments, wilderness areas, mineral reserves, Indian reservations, fish and wildlife preserves, and grazing land (U.S. Department of Commerce, 1984a; 1984b, pp. 12, 204, 657).