The USS Vallejo was a Federation California-class starship operated by Starfleet in the late 24th century.
In 2381, the Vallejo was rallied by Beckett Mariner to create an armada of California-class starships sent to defend their sister ship, the USS Cerritos, from the USS Aledo. After successfully destroying the Aledo, the armada went to Douglas Station. (LD: "The Stars At Night")
The Vallejo was presumably named for Vallejo, California.