Poston Butte, formerly called Primrose Hill, is a hill located along Hunt Highway in Florence, Pinal County, Arizona, United States,[3] near the eastern end of the Santan Mountains.

[4] Geologically, it is characterized by basalts overlying altered granite.

[5] This hill is noted for having the pyramidal tomb of Charles Debrille Poston at its summit.

Poston lobbied President Lincoln and Congress to create the Territory of Arizona[6] and was appointed Superintendent of Indian Affairs because of his familiarity with the Native populations of the area.

[7] The tomb can be accessed by a 0.6-mile (0.97 km) trail starting from the trailhead near Hunt Highway.