Poston Butte, a hill near the eastern end of Arizona’s Santan Mountains along Hunt Highway in Florence, is both a local landmark and a site of territorial memory. Formerly called Primrose Hill, it is geologically marked by basalt over altered granite. Its most notable feature is the pyramidal summit tomb of Charles Debrille Poston, a leading figure in early Arizona history. Poston helped secure the creation of the Territory of Arizona by lobbying President Lincoln and Congress, and he later served as Superintendent of Indian Affairs because of his familiarity with Native peoples in the region. A short trail leads to the tomb at the summit.