Livermore is a city in Alameda County, California. With a 2020 population of 87,955, Livermore is the most populous city in the Tri-Valley, giving its name to the Livermore Valley. It is located on the eastern edge of California's San Francisco Bay Area, making it the easternmost city in the area. The current mayor is John Marchand. Livermore was platted and registered on November 4, 1869, as a railroad town by William Mendenhall and named for Robert Livermore, Mendenhall's friend and a local rancher who settled in the area in the 1840s. It is the home of the Lawrence Livermore National Laboratory, for which the chemical element livermorium is named (and thus, placing the city's name in the periodic table). It is also the California site of Sandia National Laboratories, which is headquartered in Albuquerque, New Mexico. Its south side is home to local vineyards, and its downtown district is being redeveloped. The United States Census Bureau defines an urban area of Tri-Valley-area cities, with Livermore as the principal city: the Livermore–Pleasanton–Dublin, CA urban area had a 2020 population of 240,381, making it the 167th largest in the United States.