Idaho Code § 31-129
Jerome county is described as follows: beginning at the northwest corner of section five (5), township seven (7) south, range sixteen (16) east, Boise meridian;
Northern boundary. Thence east thirteen (13) miles, more or less, to the northeast corner of section five (5), township seven (7) south, range eighteen (18) east, Boise meridian; thence south two (2) miles, more or less, to the southwest corner of section nine (9), township seven (7) south, range eighteen (18) east, Boise meridian; thence east one (1) mile, more or less, to the southeast corner of section nine (9), township seven (7) south, range eighteen (18) east, Boise meridian; thence south one (1) mile, more or less, to the southwest corner of section fifteen (15), township seven (7) south, range eighteen (18) east, Boise meridian; thence east fifteen (15) miles, more or less, to the northeast corner of section twenty-four (24), township seven (7) south, range twenty (20) east, Boise meridian; thence south three (3) miles, more or less, to the northeast corner, section one (1), township eight (8) south, range twenty (20) east, Boise meridian; thence east six (6) miles, more or less, to the northeast corner of section one (1), township eight (8) south, range twenty-one (21) east, Boise meridian;
Eastern boundary. Thence south following the range line between ranges twenty-one (21) and twenty-two (22) east, Boise meridian, to the center line of Snake river;
Southern boundary. Thence down the center line of the channel of said river, following its meanderings to a point where the same intersects the section line between sections seventeen (17) and eighteen (18) in township nine (9) south, range sixteen (16) east, Boise meridian;
Western boundary. Thence north to the place of beginning.
County seat-Jerome.
Idaho Code § 31-129