Solano County is a county in California and the northeastern county of the nine-county San Francisco Bay Area. Its county seat is Fairfield, and the 2020 census recorded a population of 453,491. The county forms the Vallejo–Fairfield metropolitan statistical area.
It is one of the original California counties, established in 1850 when the state was admitted to the Union. At the request of General Mariano Guadalupe Vallejo, it was named for Chief Solano of the Suisun people — also known as Sem-Yeto — who was Vallejo’s ally and was given the Spanish baptismal name Francisco Solano.
Solano County is geographically the easternmost county of the North Bay; part of it extends into the Sacramento Valley. Travis Air Force Base lies east of Fairfield.
Relevance to the case
Solano County is significant to the Zodiac case as the jurisdiction containing several early crime scenes and locations. The Lake Herman Road murders of David Arthur Faraday and Betty Lou Jensen and the Blue Rock Springs attack on Darlene Elizabeth Ferrin and Michael Renault Mageau both occurred near Vallejo, within or adjacent to the county. Benicia, California, where the Lake Herman Road killings took place, is in Solano County, and the Vallejo Police Department investigated the early attacks.