Aliso Viejo was first counted by the census in 1990
More historic than 2% of U.S. towns · #838 of 847 in California. What drives it
Most of Aliso Viejo was built recently: 0.2% of its homes predate 1940 and the median home dates from 1995. Below: maps from 1948 on and the census since 1990.
On its age, its old homes and the National Register, Aliso Viejo is more historic than 2% of U.S. towns, #838 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 Aliso Viejo’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 Aliso Viejo’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 range from D− to D. The pre-1940 share (±0.2 points) is firm at this size.
Founding year: the first census (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 Aliso Viejo’s past
Read from the archive, the National Register and the record. The page puts what stands out first.
The Acjachemen are the Indigenous people of Aliso Viejo, who lived in the area for thousands of years. The people established numerous villages along Aliso Creek as well dividing the Acjachemen and the Tongva. With the arrival of settlers, the Acjachemen village sites would later become the southern areas of the Moulton Ranch.
The planned community of Aliso Viejo's original 6,600 acres (2,700 ha) were once part of the 26,000-acre (11,000 ha) Moulton Ranch, owned by the Moulton family, who took title in the 1890s to Rancho Niguel, originally granted to Juan Avila by the Mexican government in 1842. Over the years, portions of the ranch were sold and became Leisure World, Laguna Hills and Laguna Niguel.
The Aliso Viejo post office opened in 1990, the earliest record of the town by name (U.S. post office records).
How does Aliso Viejo rank for history?
Aliso Viejo is more historic than 2% of U.S. towns, #838 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 Aliso Viejo?
0.2% of Aliso Viejo’s homes were built before 1940 (Census estimate), against a typical 3.4% for a California town; the median home was built in 1995.
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 (4), Wikipedia, Wikidata and Wikipedia for famous people, U.S. Geological Survey historical maps, U.S. Census counts (via Wikipedia) 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.
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