Tri-Valley takes its name from the three adjacent valleys that make up the region: Amador, Livermore, and San Ramon. Nestled in these golden valleys are the historic communities of Pleasanton, Livermore, Dublin, San Ramon, and Danville. The area has welcomed travelers since the California Gold Rush, when the region was the main route from San Francisco to the Sierra Foothills. And though Tri-Valley is rooted in rich history, the region is most widely known for its modern amenities and authentic hospitality.

The legends of early California and the American West are captured in the colorful history of Tri-Valley. Early Native American villages, Spanish mission culture, Spanish land-grant ranchos, the California Gold Rush, the transcontinental railroad, early movie production, World War II, and the nuclear age have all been an integral part of shaping the region. The early Wild West, with its ranching and farming, has evolved into an area lush with historic as well as contemporary significance. Quaint historic districts, and even historically distinguished modern business centers make up the region's historic landscape.

Tri-Valley is home to the nationally recognized historic sites of Eugene O'Neill's Tao House, Ravenswood, and Forest Home Farms. Tao House offers visitors an intimate look at the life and home of America's only Nobel Prize winning playwright, Eugene O'Neill. He and his wife built the house in the Town of Danville, and it was there that he completed his most famous plays, "The Iceman Cometh," "Long Day's Journey Into Night," and "A Moon for the Misbegotten." The properties of Ravenswood and Forest Home Farms are open to the public for tours, inviting guests to experience life as it was from the late 1880's and early 1900's. Additionally, Forest Home Farms is now home to the City of San Ramon's Saturday farmers markets.

Local history has been colored by many things, but tales of ghosts and the supernatural have remained among the most popular with residents and visitors. The ghosts of Main Street in Pleasanton are offered up on the wildly popular "Ghost Walk", given each year around Halloween. Guided tours include tales of modern business men and women who have seen and heard peculiar things that can only be attributed to a world beyond the physical.