Alameda Island is an island located in the

San Francisco Bay San Francisco Bay is a large tidal estuary in the U.S. state of California, and gives its name to the San Francisco Bay Area. It is dominated by the big cities of San Francisco, San Jose, and Oakland. San Francisco Bay drains water f ...

California California is a state in the Western United States, located along the Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the most populous U.S. state and the 3rd largest by area. It is also the m ...

. It is south and west of, and adjacent to,

Oakland Oakland is the largest city and the county seat of Alameda County, California, United States. A major West Coast port, Oakland is the largest city in the East Bay region of the San Francisco Bay Area, the third largest city overall in the Bay ...

, and across the bay eastward from

San Francisco San Francisco (; Spanish for " Saint Francis"), officially the City and County of San Francisco, is the commercial, financial, and cultural center of Northern California. The city proper is the fourth most populous in California and 17t ...

. Located on the island is most of the city of

Alameda An alameda is a street or path lined with trees () and may refer to: Places Canada * Alameda, Saskatchewan, town in Saskatchewan ** Grant Devine Dam, formerly ''Alameda Dam'', a dam and reservoir in southern Saskatchewan Chile * Alameda (Santia ...

, a city in

Alameda County Alameda County ( ) is a county located in the U.S. state of California. As of the 2020 census, the population was 1,682,353, making it the 7th-most populous county in the state and 21st most populous nationally. The county seat is Oakland. Alam ...

. A very small western tip of the island's territory is technically part of

, however, this is uninhabited and is not separately managed. Once located on the island was the

Naval Air Station Alameda Naval Air Station Alameda (NAS Alameda) was a United States Navy Naval Air Station in Alameda, California, on San Francisco Bay. NAS Alameda had two runways: 13–31 measuring and 07-25 measuring . Two helicopter pads and a control tower were ...

, a defunct naval air station. The island was originally a peninsula and a part of Oakland and is now separated from the mainland by the Oakland Estuary. The island is connected to the mainland by six bridges: the Park Street Bridge, the Fruitvale Railroad Bridge, the Miller Sweeney Road Bridge, the High Street Bridge, the Bay Farm Island Bridge, and the Bayfarm Island Bicycle Draw Bridge. The Posey and Webster Street tubes also connect Oakland to Alameda Island.

History

The island was originally a

peninsula A peninsula (; ) is a landform that extends from a mainland and is surrounded by water on most, but not all of its borders. A peninsula is also sometimes defined as a piece of land bordered by water on three of its sides. Peninsulas exist on a ...

connected to Oakland. Much of it was low-lying and marshy, but on higher ground, the peninsula and adjacent parts of what is now downtown Oakland were home to one of the largest coastal oak forests in the world. The area was therefore called ''Encinal'', Spanish for "oak grove". ''Alameda'' is Spanish for "grove of poplar trees" or "tree-lined avenue", and was chosen in 1853 by popular vote. The inhabitants at the time of the arrival of the Spanish in the late 18th century were a local band of the

Ohlone The Ohlone, formerly known as Costanoans (from Spanish meaning 'coast dweller'), are a Native American people of the Northern California coast. When Spanish explorers and missionaries arrived in the late 18th century, the Ohlone inhabited the ...

tribe. The peninsula became part of the vast Rancho San Antonio granted to Luis Peralta by the viceroyalty under King

Ferdinand VII of Spain , house = Bourbon-Anjou , father = Charles IV of Spain , mother = Maria Luisa of Parma , birth_date = 14 October 1784 , birth_place = El Escorial, Spain , death_date = , death_place = Madrid, Spain , burial_p ...

. The grant was later confirmed by the new

Republic of Mexico Mexico ( Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guate ...

upon its independence from Spain. Over time, the place became known as Bolsa de Encinal or Encinal de San Antonio. The island was created in 1902 with the opening of a canal on the south side to enhance tidal scouring to keep the estuary to the north cleared for shipping. Landfill was added around the island and stopped once the island had been extended over the San Francisco border. The island contains many Victorian homes built in the late 1800s and early 1900s. Nearly the entire island has been developed. There are several miles of beaches along the south side.

References

External links

{{San Francisco Bay watershed, state=autocollapse *Island Islands of Alameda County, California Islands of Northern California Geography of the San Francisco Bay Area Islands of San Francisco Bay Landforms of the San Francisco Bay Area