On its age, its old homes and the National Register, San Tan Valley is among the newest of U.S. towns, #134 of 140 in Arizona. Its National Register listings hold the grade up; its age pulls it down.
D−
HistoryA character grade: shown, never part of San Tan Valley’s overall grade.
Among the 400 U.S. cities of 100,000 or more, San Tan Valley ranks #399 on History.
Few Arizona towns list much on the Register (a typical Arizona town has 0.1 per 10,000 residents, the U.S. 2.4), so San Tan Valley’s 0.0 sits below most of its state (29% of Arizona towns have fewer) while its 0 listings outnumber those of 23% of U.S. towns.
Newer cities are common at San Tan Valley’s size: in the typical U.S. city of 100,000 or more, 5% of homes predate 1940.
NoteThe founding year comes from Wikidata alone; no second source gives 2009.
How sure. Graded on any two of the three inputs instead, the letter would still be D−. The pre-1940 share (±0.1 points) is firm at this size.
Founding year: Wikidata (other dates in Quick answers). Homes: Census ACS 2020–24. National Register: National Park Service, May 2026 list; each listing counted once (boundary changes and added documentation belong to their listing), and a historic district counts its contributing buildings. How TownRatings grades history →
What stands out about San Tan Valley’s past
Read from the archive, the National Register and the record. The page puts what stands out first.
Every edition of the U.S. Geological Survey’s map of San Tan Valley. Tap a year, or press play to watch the town change.
1907Sacaton sheet · 1:62,500
U.S. Geological Survey historical topographic maps (public domain), via Esri’s collection of the scans. The red ring marks the center of San Tan Valley.
Places that used to be
Old corners
Old hamlets and crossroads still carry their names on the map.
Hamlets and corners on the map
Cimmaron Trails Mobile Home ParkLinks Estates Mobile Home ParkLos Hermanos Mobile Home ParkMagmaPleasant Valley Mobile Home Park
Places and cemeteries from the USGS Geographic Names Information System (2021).
San Tan Valley derives its name from the nearby San Tan Mountains. San Tan Valley was picked as the name for the area based on an informal public poll commissioned by now former Pinal County Supervisor Bryan Martyn. Previously referred to as San Tan Heights, San Tan Foothills, Greater San Tan and simply the San Tan Area, the community lacked any official name and residents used nearby Queen Creek for their mailing addresses. This practice led to confusion, as the Town of Queen Creek is located primarily in neighboring Maricopa County. To coincide with the addition of a new ZIP Code for the community on July 1, 2009, the United States Postal Service was petitioned to provide the area with a new name. As part of the initial request, "Bella Vista" name was submitted to the postal service, drawing the ire of some local residents who opposed the suggested name. In response, the Greater San…
San Tan Valley is among the newest of U.S. towns, #134 of 140 in Arizona. The History grade combines the town’s founding era, the share of homes built before 1940 and its National Register listings. It’s a character grade, so it isn’t part of the overall grade. How it works.
How old are the homes in San Tan Valley?
0.0% of San Tan Valley’s homes were built before 1940 (Census estimate), against a typical 0.4% for an Arizona town; the median home was built in 2007.
Founding dates: Wikidata, Wikipedia, the U.S. post office records of Blevins & Helbock (CC0) and the Census. Homes by year built: Census ACS 2020–24. National Register of Historic Places: National Park Service (list of May 22, 2026). Old photos, postcards and papers: Wikimedia Commons, the Library of Congress and other public archives, credited on each item’s page. Maps: U.S. Geological Survey historical topographic maps (via Esri) and Sanborn fire-insurance maps (Library of Congress). History text and census tables: Wikipedia (CC BY-SA 4.0). Places that used to be: USGS Geographic Names Information System (2021).
From Wikipedia, U.S. Geological Survey historical maps and the USGS Geographic Names Information System. Archive images are copied here with their credits and licenses, shown on each photo’s page. Refreshed monthly.
