The name has since then been applied to numerous locations, including a town in the Catalonia region of Spain, as well as the transverse mountain range of Santa Susana in Southern California, after which the town is named.
How historic is Santa Susana?
B−
More historic than 50% of U.S. towns, on its age, its old homes and the National Register.
On its age, its old homes and the National Register, Santa Susana is more historic than 50% of U.S. towns. Its share of homes from before 1940 holds the grade up; its National Register listings pull it down.
B−
HistoryA character grade: shown, never part of Santa Susana’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 Santa Susana’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 two of the three inputs, so a change in either one moves the letter more than it would with three. The pre-1940 share is a Census survey estimate (±14.9 points).
Founding year: our sources. 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 Santa Susana’s past
Read from the archive, the National Register and the record. The page puts what stands out first.
The hills of and immediate foots of the Santa Susana Mountains have been inhabited for thousands of years, proven by Chumash artifacts found by the Santa Susana Depot and Chumash pictographs dating to 500 AD in the Burro Flats Painted Cave. The area has likely been populated by Native-American peoples for as much as 8,000 years-12,000 years ago The Burro Flats Painted Cave, now situated on the protected private Santa Susana Field Laboratory property, was the setting for a winter solstice ritual for the Ventureño Chumash people. The cave, which is on the back wall of a sandstone shelter about 16 ft long and 4 ft high, was discovered at the turn of the 20th century The Chumash of Santa Susana were unlike other settlements in the Simi Valley not only located near other Ventureño Chumash settlements, but the Chumash here traded with the Tataviam people who also settled in the Santa Susana M…
Santa Susana is more historic than 50% of U.S. towns. 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 Santa Susana?
22% of Santa Susana’s homes were built before 1940 (Census estimate, ±14.9 points), against a typical 3.4% for a California town; the median home was built in 1978.
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.
