Grantsville, UT

ZIP code 84029 covers a sparsely populated desert region of western Tooele County, centered on Dugway. Its most prominent site is Dugway Proving Ground, a large U.S. Army research and testing installation. Other notable local landmarks include the Dugway Geode Beds, known for collectible geodes, and Simpson Springs Pony Express Station, a preserved stop on the historic mail route. The area is remote, and access to the proving ground is restricted.