Ariz. Rev. Stat. § 11-115
Yavapai county, the county seat of which is Prescott, is bounded as follows:
Commencing at the point where the thirty-fourth parallel of north latitude, as defined by the Thompson survey of 1924, and the summit of the Mazatzal mountains intersect; thence northerly along the summit of the Mazatzal mountains to the summit of the mountain known as and called "North Peak;" thence due west to the center of the channel of the Verde river; thence northerly along the center of the channel of the Verde river to the center of the channel of the mouth of Fossil creek; thence up Fossil creek along the center of the channel to the east line of range seven east, Gila and Salt River Guide meridian; thence north on such line to the fourth standard parallel north; thence west along such parallel to the east line of range five east; thence north on such line to the north line of township eighteen north; thence west on such line to the Gila and Salt river meridian; thence north on such meridian to the fifth standard parallel north; thence west on such parallel to the east line of range two west; thence north on such line to a point one mile north of the center of the right-of-way of the Atchison, Topeka & Santa Fe railway as it existed in 1891; thence westerly in a line one mile north and parallel with the center of the right-of-way to the meridian of one hundred thirteen degrees twenty minutes west longitude, as defined by the Mohave-Yavapai county boundary survey of 1908; thence south along the meridian line as surveyed and along the eastern boundaries of Mohave and La Paz counties to the point where such meridian line intersects the thirty-fourth parallel north latitude, as defined by the Thompson survey of 1924, being the northwest corner of Maricopa county; thence east on the thirty-fourth parallel north latitude, as defined, and along the northern boundary of Maricopa county to the point where the Hassayampa river intersects such parallel; thence southeasterly in a direct line following the Thompson survey of 1924 to a point in the Agua Fria river two miles southerly and below the mouth of Humbug creek; thence northerly up the Agua Fria river to a point two miles southerly and below the place where the residence of J. W. Swilling stood on January 31, 1877; thence easterly in a direct line, following the Thompson survey of 1924, to the point where the thirty-fourth parallel north latitude, as defined by such survey, intersects the Verde river; thence east on the thirty-fourth parallel north latitude, as surveyed, to the summit of the Mazatzal mountains, the point of beginning.
A.R.S. § 11-115