Cal. Gov. Code § 23123
The boundaries of Mendocino County are as follows:
Beginning at the southwest corner of Humboldt; thence east on the southern line of Humboldt to the west boundary of Trinity; thence southerly along said west boundary of Trinity two miles more or less to the southwest corner of said county; thence east along the southern boundary of Trinity to the summit of the Coast Range Mountains, forming the southeast corner of Trinity and the northeast corner of Mendocino and being the western boundary of Tehama; thence southerly along the said western boundary of Tehama to the southwest corner of the said county which is also the northwest corner of Glenn County; thence south along the half section line running south through Secs. 2, 11, 14, and 23 to the middle of said Sec. 23 in T. 22 N., R. 10 W., M. D. B. & M.; thence east along the half section line through Secs. 23 and 24 to the southeast corner of the northeast quarter of Sec. 24; thence south on the range line between R. 9 and 10 W., to the southwest corner of Sec. 32 in T. 22 N., R. 9 W.; thence east along the line between and dividing Secs. 5 and 32 to the southeast corner of said Sec. 32;
Thence south on the line between and dividing Secs. 4 and 5, 8 and 9, 16 and 17, 20 and 21, 28 and 29, 32 and 33, all in T. 21 N., R. 9 W., M. D. B. & M., to the southeast corner of Sec. 32; thence east on the line dividing T. 20 and 21 N., R. 9 W., the line being the fourth standard parallel line north, 775 feet, more or less, to the northeast corner of Sec. 5 in T. 20 N., R. 9 W.; thence south along the line between and dividing Secs. 4 and 5, 8 and 9, 16 and 17, 20 and 21, 28 and 29, 32 and 33, all of T. 20 N., R. 9 W.; thence continuing south along the line between and dividing Secs. 4 and 5 of T. 19 N., R. 9 W., to the southeast corner of the northeast quarter of said Sec. 5, T. 19 N., R. 9 W.; thence west along the said half section line through Sec. 5 and then through Secs. 1 and 2 in T. 19 N., R. 10 W., M. D. B. & M., to a point on said line due north from the monument on top of Mount Hull, established by T. P. Smythe and R. P. Hammond and party on October 20, 1885, and approved by H. J. Willey, Surveyor-General of the State of California, on December 23, 1885; thence due south to said monument; thence due south to the half section line running east and west through Sec. 11, T. 19 N., R. 10 W., M. D. B. & M.; thence west along said half section line through Secs. 11, 10, 9, 8, and 7 of said township, range, base and meridian;
And thence through Sec. 12, T. 19 N., R. 11 W., M. D. B. & M.; to the center of said Sec. 12; thence south one-half mile to the quarter section corner on the south boundary of said Sec. 12; thence west one mile to the quarter section corner between Secs. 11 and 14, said township and range; thence south one-half mile to the center of said Sec. 14; thence west one mile to the center of Sec. 15, said township and range; thence south along the half section line running through Secs. 15, 22, 27, and 34, to the quarter section corner on the south line of Sec. 34, said T. 19 N., R. 11 W., M. D. B. & M.; thence west along the township line between T. 18 and 19 N., R. 11 W., M. D. B. & M.; to the northwest corner of lot three, Sec. 3, T. 18 N., R. 11 W., M. D. B. & M.; thence south along the line dividing the east half of the west half from the west half of the west half of said Sec. 3, a distance of one mile to the south boundary line of said Sec. 3; thence west along the south boundary of said Sec. 3, to the corner common to Secs. 3, 4, 9, and 10, said township and range; thence south along the section line between Secs. 9, 10, and 15, and 16, a distance of two miles to the corner of Secs. 15, 16, 21, and 22, said township and range; thence east along the line between Secs. 15 and 22, to the corner of Secs. 14, 15, 22, and 23, said T. 19 N., R. 11 W.;
Thence south along the section line between Secs. 22 and 23, and 26 and 27, a distance of two miles to the corner of Secs. 26, 27, 34, and 35, said township and range; thence east along the section line between Secs. 26 and 35, a distance of one-half mile to the quarter section corner between last mentioned sections; thence south along the half section line one mile to the quarter section corner on the south boundary of Sec. 35, T. 18 N., R. 11 W., M. D. B. & M.; thence east along the township line on the north boundary of T. 17 N., R. 11 W., M. D. B. & M., to the northeast corner of Sec. 2, said township and range; thence south along the section line between Secs. 1 and 2, and 11 and 12, a distance of two miles to the corner of Secs. 11, 12, 13, and 14; thence east along the section line between Secs. 12 and 13, a distance of one-half mile to the quarter section corner between said sections; thence south along the half section line a distance of one mile to the quarter section corner between Secs. 13 and 24; thence east along the section line between said Secs. 13 and 24, a distance of one-half mile to the line between T. 17 N., R. 10 and 11 W., M. D. B. & M.; thence south along said line a distance of three miles to the corner of T. 16 and 17 N., R. 10 and 11 W., M. D. B. & M.;
Thence east along the north line of T. 16 N., R. 10 W., M. D. B. & M., to the northeast corner of Sec. 6, said township and range; thence south along the section line between Secs. 5 and 6 and 7 and 8, a distance of one and one-half miles to the quarter section corner between Secs. 7 and 8; thence east along the half section line a distance of one-half mile to the center of said Sec. 8; thence south along the half section line a distance of one and one-half miles to the quarter section corner between Secs. 17 and 20, said township and range; thence west along the section line a distance of one mile to the quarter section corner between Secs. 18 and 19; thence south along the half section line a distance of one mile to the quarter section corner between Secs. 19 and 30; thence west one-half mile more or less, to the corner of Secs. 19, 24, 25, and 30, T. 16 N., R. 10 and 11 W., M. D. B. & M.; thence south along the range line between said ranges ten and eleven, a distance of one-half mile to the quarter section corner on the east boundary of Sec. 25, T. 16 N., R. 11 W.; thence west along the north line of lot three, Sec. 25, said township and range, a distance of one-quarter mile, more or less, to the northwest corner of said lot three; thence south along the west line of lots three and four, said Sec. 25, a distance of one-half mile to the south boundary of said Sec. 25; thence west along the south line of said Sec. 25 to the quarter section corner between Secs. 25 and 36, said township and range; thence south along the half section line, a distance of one-half mile to the center of said Sec. 36; thence west along the half section line a distance of one-fourth mile to the northwest corner of the northeast quarter of the southwest quarter of said Sec. 36;
Thence south along the west line of the NE. 1/4 of the SW. 1/4 and the west line of lot six of said Sec. 36, to the north boundary of T. 15 N., R. 11 W., M. D. B. & M.; thence west along said township line to the quarter section corner on the north boundary of Sec. 2, T. 15 N., R. 11 W., M. D. B. & M.; thence south along the half section line to the quarter section corner between Secs. 2 and 11, said township and range; thence west along the section line between Secs. 2 and 11 one-quarter mile to the northwest corner of the east half of the NW. 1/4 of said Sec. 11; thence south along the west line of the said east half of the NW. 1/4 of Sec. 11, a distance of one-half mile to the half section line running east and west through said Sec. 11; thence west along said half section line one and three-quarters miles to the center of Sec. 9, said township and range; thence south along the half section line a distance of two and one-half miles to the quarter section corner between Secs. 21 and 28; thence west along the section line a distance one-half mile to the corner of Secs. 20, 21, 28, and 29; thence south along the section line a distance of two miles to the line on the north boundary of T. 14 N., R. 11 W., M. D. B. & M.; thence east along said township line a distance of three and sixty-five hundredths chains to the northwest corner of Sec. 4, T. 14 N., R. 11 W., M. D. B. & M.;
Thence south along the section line a distance of one mile to the corner of Secs. 4, 5, 8, and 9, said township and range; thence west along the section line a distance of one-half mile to the quarter section corner between Secs. 5 and 8; thence south along the half section line to the quarter section corner on the south boundary of Sec. 8; thence east along the section line between Secs. 8 and 17, a distance of five and ninety hundredths chains more or less, to the quarter section corner on the north boundary of Sec. 17; thence south along the half section line a distance of one-half mile to the center of said Sec. 17; thence east along the half section line a distance of one-half mile to the quarter section corner between Secs. 16 and 17; thence south along the section line a distance of one-half mile to the corner of Secs. 16, 17, 20, and 21; thence east along the section line a distance of one mile to the corner of Secs. 15, 16, 21, and 22; thence south along the section line a distance of one mile to the corner of Secs. 21, 22, 27, and 28; thence east along the section line a distance of one-half mile to the quarter section corner between Secs. 22 and 27; thence south along the half section line two miles to the north boundary of T. 13 N., R. 11 W., M. D. B. & M.; thence east along the township line one-half mile to the northwest corner of Sec. 2, said township and range; thence south along the section line a distance of one-half mile to the quarter section corner between Secs. 2 and 3; thence east along the half section line a distance of one-half mile to the center of said Sec. 2; thence south along the half section line a distance of one-half mile to the quarter section corner between Secs. 2 and 11;
Thence east along the section line a distance of one-half mile to the corner of Secs. 1, 2, 11, and 12; thence south along the section line a distance of one-half mile to the quarter section corner between Secs. 11 and 12; thence east along the half section line a distance of one-half mile to the center of said Sec. 12; thence south along the half section line a distance of one-quarter mile to the corner of lots two, three, six, and seven of said Sec. 12; thence east along the south line of lots one and two of said Sec. 12, a distance of one-half mile to the line between T. 13 N., R. 11 and 12 W., M. D. B. & M.; thence north along said range line a distance of nine and twenty-five hundredths chains to the southwest corner of Sec. 5, T. 13 N., R. 10 W., M. D. B. & M.; thence east along the section line a distance of 89 chains to the corner of Secs. 4, 5, 8, and 9; thence south along the section line a distance of one mile to the corner of Secs. 8, 9, 16, and 17; thence east along the section line a distance of one-half mile to the quarter section corner between Secs. 9 and 16; thence south along the half section line a distance of two and one-half miles to the center of Sec. 28; thence east along the half section line a distance of one-half mile to the quarter section corner between Secs. 27 and 28; thence south along the section line a distance of one mile to the quarter section corner between Secs. 33 and 34; thence east along the half section line, a distance of one-half mile to the center of Sec. 34;
Thence south along the half section line a distance of one-half mile to the north boundary of T. 12 N., R. 10 W., M. D. B. & M.; thence east along said township line a distance of 55 chains to the northeast corner of Sec. 3, T. 12 N., R. 10 W.; thence south along the section line a distance of one and one-half miles to the quarter section corner between Secs. 10 and 11; thence east along the half section line a distance of two miles to the line between T. 12 N., R. 9 and 10 W., M. D. B. & M.; thence south along the line between said ranges nine and ten a distance of one-half mile to the corner of Secs. 7, 12, 13, and 18, said townships and ranges; thence east along the section line a distance of one mile to the corner of Secs. 7, 8, 17, and 18, T. 12 N., R. 9 W., M. D. B. & M.; thence south along the section line a distance of one mile to the corner of Secs. 17, 18, 19, and 20; thence east along the section line a distance of one mile to the corner of Secs. 16, 17, 20, and 21; thence south along the section line a distance of one-half mile to the quarter section corner between Secs. 20 and 21; thence east along the half section line a distance of one mile to the quarter section corner between Secs. 21 and 22; thence south along the section line a distance of one-half mile to the corner of Secs. 21, 22, 27, and 28; thence east along the section line a distance of one mile to the corner of Secs. 22, 23, 26, and 27; thence south along the section line a distance of one-half mile to the quarter section corner between Secs. 26 and 27; thence east along the half section line a distance of one mile to the quarter section corner between Secs. 25 and 26; and thence south along the section line a distance of one-half mile to the corner of Secs. 25, 26, 35, and 36, T. 12 N., R. 9 W., M. D. B. & M., said point being the southeast corner of Mendocino and the northeast corner of Sonoma; thence westerly on the northern line of Sonoma to the Pacific Ocean; thence northerly along the ocean shore to the place of beginning.
Ca. Gov. Code § 23123