Alamo, CA Homes for Sale. Alamo, an unincorporated community of Contra Costa County is nestled at the base of Mt. Diablo and surrounded by gorgeous oak-studded hillsides, views of the Las Trampas Ridgeline, and access to many hiking and walking trails including the popular Iron Horse Trail that runs through the Tri Valley. Quiet and peaceful neighborhoods including Alamo Springs, Round Estates North, White Gate, and Bryan Ranch, and the gated Stonegate and Jones Ranch Estates are home to some of the Tri-Valley’s most exclusive custom estates on sprawling lots. Wrapped in a country and rural ambiance, the neighborhoods are also conveniently close to many shopping and dining options in the charming Alamo Plaza, nearby downtown Danville, and Walnut Creek in addition to freeway access, Walnut Creek BART and commute routes into San Francisco and Silicon Valley. Alamo’s 18.5 square miles is also home to highly-acclaimed schools in the San Ramon Valley Unified School District, and the famed world-class Round Hill Country Club that offers championship golf, tennis, swimming, a fitness center, bocce courts, and exceptional clubhouse amenities for private events.