Vallejo (/vəˈleɪ.oʊ/ or /vəˈleɪhoʊ/; Spanish: [baˈʎexo]) is a city in Solano County, California, located in the North Bay region of the San Francisco Bay Area. The population was 115,942 at the 2010 census. It is the tenth most populous city in the San Francisco Bay Area, and the largest in Solano County. Vallejo sits on the northeastern shore of San Pablo Bay. The city is named after General Mariano Guadalupe Vallejo, a native Californio, leading proponent of California's statehood, and one of the first members of the California State Senate; the neighboring city of Benicia is named for his wife, Francisca Benicia Carillo de Vallejo.
Vallejo is home to the Six Flags Discovery Kingdom theme park, the now-defunct Mare Island Naval Shipyard, and the regional office for Region 5 of the United States Forest Service. The colleges and universities in Vallejo are California Maritime Academy, the Vallejo Center campus of Solano Community College, and Touro University California. Ferry service runs from a terminal on Mare Island Strait to San Francisco, through the BayLink division of SolTrans.
Vallejo has twice served as the capital of the state of California: once in 1852 and again in 1853, both periods being brief. The State Capitol building burned to the ground in the 1880s and the Vallejo Fire Department requested aid from the Fire Department at Mare Island Naval Shipyard. As there were no bridges at that time, the Mare Island Fire Department had to be ferried across the Napa River, arriving to find only the foundation remaining. This was the first recorded mutual aid response in the state of California.
Some of the first Europeans drawn to the Vallejo area were attracted by the sulfur springs; in the year 1902 the area was named Blue Rock Springs. It was also known as White Sulfur Springs and that was the name of the road leading to it from town, today shortened to "Springs Road".