Located in a pine-covered valley in the San Gabriel Mountains, the Wrightwood area was first developed as cattle ranches in the 19th century by Nathan and Truman Swarthout. Later, the main ranch, owned by Sumner Wright, was broken up into residential and commercial lots, and by the 1920s a community had taken root. Early ski enthusiasts discovered the north-facing slopes of the San Gabriels above the Swarthout Valley. Until 1937, the ski area, originally known as Big Pines, was part of a Los Angeles County park. After WWII, Big Pines opened their 1946-47 ski season with a new chairlift and the Sepp Benedikter Ski School (according to their ad in the February 1947 issue of Western Skiing magazine). Highways were built connecting to the major routes in the Cajon Pass, making Wrightwood accessible without serious mountain driving.