On its age, its old homes and the National Register, O'Hara Township is more historic than 56% of U.S. towns, #652 of 1,035 in Pennsylvania. Its National Register listings hold the grade up; its age pulls it down.
B
HistoryA character grade: shown, never part of O'Hara Township’s overall grade.
Pennsylvania towns list about as much on the Register as the country (a typical Pennsylvania town has 2.1 per 10,000 residents, the U.S. 2.4), so O'Hara Township’s 3.3 sits near the middle of its state (62% of Pennsylvania towns have fewer) while its 3 historic buildings outnumber those of 65% of U.S. towns.
NoteThe founding year comes from Wikidata alone; no second source gives 1875.
How sure. Graded on any two of the three inputs instead, the letter would range from C+ to B+. The pre-1940 share is a Census survey estimate (±5.6 points).
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 O'Hara Township’s past
Read from the archive, the National Register and the record. The page puts what stands out first.
Lost post offices, old corners and burying grounds
Another post office, Blawnox, opened and closed inside today’s town.
Hamlets and corners on the map
Fairview HeightsMontrose HillPark View
3cemeteries and burying grounds inside O'Hara Township
GreenwoodSaint Mary'sTree of Life
US Post Offices dataset (Blevins & Helbock, CC0). Places and cemeteries from the USGS Geographic Names Information System (2021).
The story so far
O'Hara Township, in brief
Wikipedia doesn’t have a history of O'Hara Township yet. The photos, dates and memories neighbors add here are how it gets written.
O'Hara Township is a township with home rule status in Allegheny County, Pennsylvania, United States, six miles northeast of Downtown Pittsburgh. The community was long organized as a township, and retains "Township" in its official name, but adopted a home rule charter in 1973 (taking effect on January 5, 1976) and is no longer subject to the Pennsylvania Township Code. The population was 9,288 at the 2020 census. It is named for James O'Hara, an early American industrialist in western Pennsylvania, and a Revolutionary War general.
O'Hara Township was established in 1875. Between the 2010 and 2020 censuses its population grew from 8,407 to 9,284 (+10%).
Intro from Wikipedia. Population: U.S. Census Bureau.
Timeline
O'Hara Township, 1875 to 1953
Woven from the archive, old maps, post office records, the National Register and the people born here.
The U.S. Geological Survey’s map of O'Hara Township.
1904Pittsburgh 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 O'Hara Township.
On the National Register
1 historic place in O'Hara Township
The country’s official list of buildings and places worth saving.
place listed
1
National Historic Landmarks
0
none yet
historic buildings protected
3
each building in a district counts
first listed
2000
Allegheny River Lock and Dam No. 2
Structures
Architectural styles listings
Late Nineteenth and Early Twentieth Century Revival1
In 1875, according to Wikidata. O'Hara Township’s post office opened in 1920, and the census of 1880 counted 2,498 people here.
How does O'Hara Township rank for history?
O'Hara Township is more historic than 56% of U.S. towns, #652 of 1,035 in Pennsylvania. 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.
What is on the National Register in O'Hara Township?
One place: the Allegheny River Lock and Dam No. 2 (listed 2000).
How old are the homes in O'Hara Township?
15% of O'Hara Township’s homes were built before 1940 (Census estimate, ±5.6 points), against a typical 18% for a Pennsylvania town; the median home was built in 1966.
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 Wikidata (1), the National Register of Historic Places (1), Wikidata and Wikipedia for famous people, 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.
