California Code, Government Code - GOV § 23142

The boundaries of Santa Barbara County are as follows:

Beginning at the southwestern corner of Ventura; thence northerly, on the westerly line of Ventura to the point of intersection with the southern line of T. 10 N., San Bernardino base; said point being on the southern boundary of Kern and being the common corner of Santa Barbara and Ventura; thence west on said township line, to the Santa Maria River; thence down said river to a point in the Pacific Ocean opposite the mouth of said river, forming the northwest corner; thence southeasterly, by the ocean shore, to the place of beginning; including the islands of Santa Barbara, San Miguel, Santa Rosa, and Santa Cruz.