Mountain House is a city in San Joaquin County, California, located west of Tracy near the Alameda County line and the Altamont Pass. It is a master-planned community whose origins are unusually recent: the plan was approved by the San Joaquin County Board of Supervisors in 1994, construction began in 2001, and Mountain House incorporated as a city in July 2024, becoming California's 483rd municipality. The population is roughly 25,000. The community was designed from the ground up around family amenities, with neighborhoods organized into villages of newer single-family homes clustered near parks, schools, and trails. Most residents own their homes, and the population skews toward families with children, giving Mountain House a cohesive, suburban character. Its housing stock is predominantly newer tract construction, generally offering more space at a lower cost than communities closer to the Bay Area. Education is provided by the Lammersville Unified School District, which is headquartered in Mountain House and serves students from Pre-K through high school, including Mountain House High School. The district also serves portions of the surrounding area west of Tracy, and its campuses are distributed throughout the community's planned villages. Mountain House's position is its defining commuter asset. Situated along the Altamont Pass, it offers the most direct drive toward the East Bay and Tri-Valley among the Tracy-area cities, and the Tracy ACE train station is a short drive away for rail commuters. The surrounding San Joaquin Valley and the pass itself provide open views and a rural backdrop at the edge of the Bay Area's suburban reach. For homebuyers, Mountain House offers new construction, planned-community amenities, strong local schools, and a strategic location for Bay Area commuting at a more accessible price point than the inner East Bay.