South Santa Clara County, situated at the south end of San Francisco Bay, was a cattle-ranching area in the 19th century. With 300 days of sun a year, it became a major agricultural and food-production center. Since the 1960s, the electronics and computer industries have transformed the Valley of the Heart's Delight into a world-class technology center. City dwellers are now taking up residence in an area once steeped in agriculture, with more than...