Cal. Gov. Code § 23140
The boundaries of San Luis Obispo County are as follows:
Beginning in the Pacific Ocean, at the northwestern corner of Santa Barbara; thence easterly, on the northern line of Santa Barbara, up the Santa Maria River, to the intersection of the southern line of T. 10 N., San Bernardino base; thence east on said line to the southeast corner of Sec. 31, in T. 10 N., R. 24 W., S. B. B. & M.; thence north on the dividing section lines between 31 and 32, 30 and 29, 19 and 20, 18 and 17, 7 and 8, 6 and 5, to the northeast corner of Sec. 6, in the said township and range; thence continuing north through T. 11 N., R. 24 W., S. B. B. & M., on the section lines between Secs. 31 and 32, 30 and 29, 19 and 20, 18 and 17, 7 and 8, 6 and 5, to the northeast corner of Sec. 6 in said township and range; thence west on the township line between T. 11 and 12 N., R. 24 W., S. B. B. & M., and along the north boundary of Sec. 6 to the northwest corner of said T. 11 N., R. 24 W., S. B. B. & M.; thence north, between Secs. 31 (in fractional T. 12 N., R. 24 W.), and Sec. 36 (in fractional T. 12 N., R. 25 W.), to the eighth standard parallel south of M. D. B. & M.;
Thence westerly on the said eighth standard parallel south to the corner common to T. 32 S., R. 22 E., and 32 S., R. 23 E., M. D. B. & M.; thence northerly, as per the United States survey, on the line between said townships and ranges, to the northeast corner of T. 32 S., R. 22 E., M. D. B. & M.; thence westerly on the north boundary of said township and range to the corner common to T. 31 S., R. 21 E., 32 S., R. 21 E., M. D. M.; thence north to the northeast corner of T. 31 S., R. 21 E., M. D. M.; thence west eight miles to the southwest corner of Sec. 35, in T. 30 S., R. 20 E.; thence north on the section line between Secs. 34 and 35, 27 and 26, 22 and 23, 15 and 14, 10 and 11, and 3 and 2, to the northeast corner of Sec. 3 in T. 30 S., R. 20 E., M. D. B. & M.; thence west four miles to the northwest corner of said last above named township and range; thence north to the northeast corner of T. 29 S., R. 19 E.; thence west to the northwest corner of said T. 29 S., R. 19 E., M. D. B. & M.;
Thence west one mile to the southeast corner of Sec. 35, T. 28 S., R. 18 E., M. D. M.; thence north to the northeast corner of Sec. 26, said township and range; thence west to the northwest corner of said Sec. 26; thence north to the northeast corner of Sec. 22; thence west to the northwest corner of Sec. 22; thence north to the northeast corner of Sec. 16; thence west to the northwest corner of Sec. 16; thence north to the northeast corner of Sec. 8; thence west to the northwest corner of Sec. 8; thence north to the township line at the northeast corner of Sec. 6; thence west to the northwest corner of T. 28 S., R. 18 E.; thence north on the range line to the northeast corner of T. 27 S., R. 17 E., M. D. B. & M.; thence west on the township line to the northwest corner of said township; thence north, on the range line between T. 26 S., R. 16 E., and T. 26 S., R. 17 E., to the northeast corner of T. 26 S., R. 16 E.; thence north on the range line between T. 25 S., R. 16 E., and T. 25 S., R. 17 E., M. D. B. & M., to the northeast corner of T. 25 S., R. 18 E., on the sixth standard parallel south of Mount Diablo base; thence west on said standard parallel and extension thereof to the Pacific Ocean; thence southerly along the shore to the place of beginning.
Ca. Gov. Code § 23140