Pinal County

The county in brief

A traveler's read on Pinal County

Eighteen ninety-two — that is the year Congress and President Benjamin Harrison set aside Casa Grande Ruins as the first archaeological-and-prehistoric reserve in the United States, the original act predating the Antiquities Act of 1906 by 14 years and establishing the legal-precedent framework that all subsequent National Monument designations would later use. The Casa Grande Great House at the monument's core is a four-story Hohokam-built coursed-caliche adobe structure raised around 1350 CE — the largest pre-contact adobe building ever constructed in North America at roughly 60 ft long, 40 ft wide, and 40 ft tall, with walls of locally-mined caliche (a calcium-carbonate-cemented hardpan) up to 4 ft thick at the base. The Hohokam abandoned the site by 1450 CE for reasons archaeologists still debate (Salt River salinization, prolonged drought, internal social collapse), and the Great House had stood roofless and weather-exposed for 500 years by the time Father Eusebio Kino documented it in his 1694 expedition journal. A steel-and-fiberglass canopy roof structure (built 1932, renewed in concrete-and-steel in 2006) now shelters the Great House from monsoon rain that would otherwise have dissolved it within decades.

Pinal County's 5,366 sq mi wrap Casa Grande (city; population 53,658, the county's largest), Florence (population 25,536, the county seat and the location of the Arizona State Prison Complex, the largest state-prison facility in the state), the Apache Trail (Arizona State Route 88, originally a freight road built 1903-1906 to supply the Roosevelt Dam construction and one of the most-cited dangerous state highways in the US with unpaved washboard sections beyond Tortilla Flat, indefinitely closed beyond Fish Creek Canyon since 2019 storm damage), the Superstition Wilderness (160,200 acres of saguaro-and-cholla Sonoran Desert under USFS Tonto NF management), and the Tonto National Forest's Globe Ranger District. Lost Dutchman State Park at the Superstition Wilderness's western base accepts rigs to 45 ft on 138 sites (most with electric and water hookups) and is the canonical RV-friendly base for Superstition Wilderness staging and the Lost Dutchman Mine folklore tour. Picacho Peak State Park (rigs to 40 ft, 85 sites, electric hookups) is the alternative I-10 base. Tonto NF permits 14-day dispersed at signed sites with rigs to 30 ft.