Tassajara Formation

Rancho San Ramon (St. Raymond Ranch in Spanish) was a 8,917-acre (36.09 km2) Mexican land grant in the northern San Ramon Valley of present-day Contra Costa County, California. Rancho San Ramon (Amador) was adjacent in the southern San Ramon Valley. It was given in 1833 by Governor Jose Figueroa to Mariano Castro and Bartolome Pacheco. Governor Figueroa granted Castro and Pacheco two square leagues of San Ramon Valley from the crest of the western ridge to the crest of the east. Castro had the northern square league, and Pacheco the southern.The grant included present-day Alamo, Danville and northern San Ramon.

Diablo Foothills Regional Park is a 1,060 acres (4.3 km2) regional park of the East Bay Regional Park District. It is located in Contra Costa County, in the East Bay region of northern California.

Monte Vista High School is a comprehensive public high school located in Danville, California, United States. It is a National Blue Ribbon school, as well as a California Distinguished School. It is fully WASC accredited. The school is located in the San Ramon Valley, approximately 35 miles (56 km) east of San Francisco, and is part of the San Ramon Valley Unified School District. Their school mascot is a mustang.

Castle Rock Regional Recreation Area is a 18,000 acres (73 km2) regional park of the East Bay Regional Park District. It is located in Contra Costa County, in the East Bay region of northern California.

The Old Borges Ranch is a 1,035 acres (419 ha) historic district in the Mt. Diablo foothills within the 2,600-acre (1,100 ha) Walnut Creek Open Space in Contra Costa County, California. A former cattle ranch, Old Borges Ranch includes multiple historic buildings, a ranger station, farm animals, and access to trails.

Alamo (Spanish: Álamo; meaning "Poplar tree") is an unincorporated community and census-designated place (CDP) in Contra Costa County, California, in the United States. It is a suburb located in the San Francisco Bay Area's East Bay region, approximately 28 miles (45 km) east of San Francisco. Alamo is equidistant from the city of Walnut Creek and the incorporated town of Danville. As of the 2020 census, the population was 15,314. Police services are provided by the Contra Costa County Office of the Sheriff. Fire and EMS services are provided by the San Ramon Valley Fire Protection District. Alamo has a median household income of $300,000 (as of 2022). In August 2007, a group of citizens launched a new initiative to incorporate the community, the latest in a series of attempts that go back to the early 1960s or before; it was defeated by referendum in March 2009. Previous failed Alamo incorporation efforts always included parts of other nearby unincorporated areas: Alamo-Danville (1964) and Alamo-Danville-San Ramon (1976).

San Ramon Valley High School is a four-year public high school located in the East Bay neighborhood of Danville, California, United States. It is a part of the San Ramon Valley Unified School District. It is a National Blue Ribbon school from the Blue Ribbon Schools Program as well as a California Distinguished School. Its rival is Monte Vista High School.

The Iron Horse Regional Trail is a rail trail for pedestrians, horse riders and bicycles in the East Bay Area in California. This trail is located in inland central Alameda and Contra Costa counties, mostly following a Southern Pacific Railroad right of way established in 1891 and abandoned in 1977. The two counties purchased the right of way at that time, intending to use it as a transportation corridor; the Iron Horse Trail was first established in 1986. In 2003, BART proposed to also use the right-of-way for a DMU line from Walnut Creek station to Tracy via Pleasanton.The trail passes through the cities of Pleasanton, Dublin, San Ramon, Danville, Alamo, Walnut Creek, Pleasant Hill and Concord. When completed, the trail will span from Livermore in central Alameda County to Suisun Bay at the northern edge of Contra Costa County, a distance of over 40 miles (64 km) connecting two counties and nine communities. The trail also directly connects to both the Dublin/Pleasanton and Pleasant Hill BART stations. The trail is maintained by the East Bay Regional Park District. It is a wheelchair accessible paved trail along with adjacent unpaved or soft trails in certain areas.The Iron Horse Regional Trail has several bridges over busy thoroughfares to help improve traffic flow; two notable ones cross over Ygnacio Valley Road in Walnut Creek and Treat Boulevard in Contra Costa Centre. Additional bridges are in the planning process. Despite initial skepticism, and even opposition, the trail is now a major transportation and recreation corridor. One million trips are made each year on the path.

The Town of Danville is located in the San Ramon Valley in Contra Costa County, California. It is one of the incorporated municipalities in California that use "town" in their names instead of "city". The population was 43,582 at the 2020 census. Since 2018, for five years in a row, Danville was named "the safest town in California".The Iron Horse Regional Trail runs through Danville. It was first a railroad that has been converted to an 80-foot (24 m) wide corridor of bike and hike trails as well as controlled intersections. Extending from Livermore to Concord, the trail passes through Danville.Danville is also home to the Eugene O'Neill National Historic Site, Village Theatre and Art Gallery, and the Museum of the San Ramon Valley.

The Danville Southern Pacific Train Depot in Danville, California is located at 205 Railroad Ave. and W Prospect Ave. It was built in 1891 on land donated by John Hartz which was erected when the Martinez line was extended south to San Ramon. The first train came on June 7, 1891. Passenger service ended in 1934. The Southern Pacific Railroad trains continued to pass through town with freight until 1978 when the line was abandoned. The building was sold in 1951 for the Danville Supply and Feed store. In June 1996, it was purchased and moved 100 yards. It was a passenger and freight station built to the design titled "Combination Station No. 22" out of standard designs of the Southern Pacific. In 2018 it houses the Museum of the San Ramon Valley. It lies along the Iron Horse Regional Trail, a rail trail formed from the converted Southern Pacific right of way.

California's 11th congressional district is a congressional district in the U.S. state of California and is represented by Nancy Pelosi. Before redistricting, the 11th district consisted of most of Contra Costa County. Mark DeSaulnier, a Democrat, represented the district from January 2015 to January 2023. Cities and CDPs in the district included Alamo, Bay Point, Blackhawk, Clayton, Concord, Diablo, El Cerrito, El Sobrante, Kensington, Lafayette, Moraga, Orinda, Pinole, Pittsburg, Pleasant Hill, San Pablo, Richmond, and Walnut Creek; most of Danville; and parts of Antioch and Martinez.Following redistricting in 2023 by the California Citizens Redistricting Commission, the 11th district is entirely in San Francisco, and includes most of the city with the exception of the Excelsior District, Visitacion Valley, Portola, and Ocean View on the city's southern edge. Former Speaker of the House Nancy Pelosi represents the new 11th district.

Area code 925 is a telephone area code in the North American Numbering Plan for a northern part of the U.S. state of California. It was created in an area code split of area code 510 in 1998. The numbering plan area comprises the inland portions of the East Bay counties of Alameda and Contra Costa.