The USS Ventura was a Federation starship operated by Starfleet that was in service during the late 24th century.
In 2381, Ensign P'jok, a former member of the Redshirts aboard the USS Cerritos, had recently transferred to the Ventura. P'jok's departure left an opening in the club on Cerritos that was temporarily filled by Brad Boimler. (LD: "The Spy Humongous")
This starship was only mentioned in dialogue.
While this ship's name suggests it could be a California-class ship, in reference to Ventura, California, it was not explicitly named as part of the fleet of ships of that class in the episode "The Stars At Night".