More historic than 20% of U.S. towns · #460 of 847 in California. What drives it
Most of Charter Oak was built recently: 3% of its homes predate 1940 and the median home dates from 1967. Below: maps from 1894 on and the census since 1980.
Founding year: the first Charter Oak post office (Blevins & Helbock, CC0).
History grade
What drives Charter Oak’s History grade
On its age, its old homes and the National Register, Charter Oak is more historic than 20% of U.S. towns, #460 of 847 in California. Its age holds the grade up; its share of homes from before 1940 pulls it down.
C−
HistoryA character grade: shown, never part of Charter Oak’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 Charter Oak’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.
How sure. Graded on any two of the three inputs instead, the letter would still be C−. The pre-1940 share is a Census survey estimate (±3.5 points). The founding year is the first post office, not a stated founding date.
Founding year: the first post office (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 Charter Oak’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 Charter Oak. Tap a year, or press play to watch the town change.
1894Pomona 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 Charter Oak.
The story so far
Charter Oak, in brief
Wikipedia doesn’t have a history of Charter Oak yet. The photos, dates and memories neighbors add here are how it gets written.
Charter Oak is an unincorporated community and census-designated place (CDP) in the San Gabriel Valley of Los Angeles County, California, approximately 26 miles (42 km) east of downtown Los Angeles. The population was 9,739 at the 2020 census, up from 9,310 at the 2010 census. Charter Oak is located in the eastern San Gabriel Valley, situated along Arrow Highway in between Covina to the south, Glendora to the north and San Dimas to the east. Residents tend to refer to the CDP portion as the "unincorporated part of Covina", or simply as "Covina". Originally a small agricultural settlement (primarily citrus orchards) centered on the intersection of Arrow Highway and Bonnie Cove Avenue, popula…
Its first post office opened in 1899. Between the 2010 and 2020 censuses its population grew from 9,310 to 9,739 (+5%).
Intro from Wikipedia. Population: U.S. Census Bureau.
Timeline
Charter Oak, 1894 to 1954
Woven from the archive, old maps, post office records, the National Register and the people born here.
The Charter Oak post office opened in 1899, the earliest record of the town by name (U.S. post office records).
How does Charter Oak rank for history?
Charter Oak is more historic than 20% of U.S. towns, #460 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 Charter Oak?
3% of Charter Oak’s homes were built before 1940 (Census estimate, ±3.5 points), against a typical 3.4% for a California town; the median home was built in 1967.
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), U.S. Geological Survey historical maps, U.S. Census counts (via Wikipedia), the US Post Offices dataset (Blevins & Helbock) 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.
2024
2019
