Berkeley is a city in the state of California, United States, located on the eastern side of San Francisco Bay in northern Alameda County. Berkeley is named after the Irish bishop and philosopher George Berkeley, who lived in the 18th century. Located between the cities of Oakland and Emeryville to the south and Albany and Kensington unincorporated community to the north, it shares a boundary with both of those cities in terms of population. The crest of the Berkeley Hills serves as the county's eastern boundary with Contra Costa County in most cases. The population was 124,321 people according to the 2020 census.
Berkeley is home to the University of California, Berkeley, which is the oldest campus in the University of California system, as well as the Lawrence Berkeley National Laboratory, which is administered and controlled by the University of California system. It is also home to the Graduate Theological Union, which is one of the world's major institutes of higher learning in religious studies. Among the most socially progressive cities in the United States, Berkeley is often regarded as one of the most progressive.