N.M. Stat. § 4-29-1
The boundaries of the county of Taos are as follows: on the south, from the first house of the town of Embudo, on the upper side, where the canyon of Picuris terminates, drawing a direct line toward the south over the mountain of Bajillo at the town of Rincones, until it reaches the front of the last house of Las Trampas, on the south side; from thence, drawing a direct line toward the east, dividing the mountain, until it reaches the junction of the rivers Mora and Sapello, and from thence to the boundary line of the territory; from the above-mentioned house of Embudo, drawing a line toward the north over the mountain, and dividing the Rio del Norte in the direction of the Tetilla de la Petaca; from thence taking a westward direction until it terminates with the boundary line of the territory; and on the north by the boundary line of the territory of New Mexico.
NMS § 4-29-1