On its age, its old homes and the National Register, Mountain House is among the newest of U.S. towns, #841 of 847 in California. Its National Register listings hold the grade up; its age pulls it down.
D−
HistoryA character grade: shown, never part of Mountain House’s overall grade.
Few California towns list much on the Register (a typical California town has 0.0 per 10,000 residents, the U.S. 2.4), so Mountain House’s 0.0 sits below most of its state (31% of California towns have fewer) while its 0 listings outnumber those of 23% of U.S. towns.
NoteThe founding year comes from Wikidata alone; no second source gives 2001.
How sure. Graded on any two of the three inputs instead, the letter would range from D− to D. The pre-1940 share (±0.2 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 Mountain House’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 Mountain House. Tap a year, or press play to watch the town change.
1914Bethany sheet · 1:31,680
U.S. Geological Survey historical topographic maps (public domain), via Esri’s collection of the scans. The red ring marks the center of Mountain House.
In 1849, Thomas Goodall erected a blue denim cloth tent to serve as a midway stopover for gold miners headed from San Francisco to the Sierra Nevada foothills via Altamont Pass. Goodall eventually built an adobe house at the eastern edge of the Diablo Range hills, calling it The Mountain House. Simon Zimmerman later acquired the stop and it became known as Zimmerman's Mountain House and became a well-known way station stop on the way to Stockton. The last remaining settlement buildings were leveled in 1940.
Mountain House is among the newest of U.S. towns, #841 of 847 in California. 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 Mountain House?
0.1% of Mountain House’s homes were built before 1940 (Census estimate), against a typical 3.4% for a California town; the median home was built in 2011.
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 Wikimedia Commons (2), 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.
2013
2013
