Armstrong County is a county located in the U.S. state of Pennsylvania. As of the 2010 census, the population was 68,941. The county seat is Kittanning. It is located northeast of Pittsburgh and Allegheny County. Armstrong County was added to the Pittsburgh Metropolitan Statistical Area in 2003.
The county was organized on March 12, 1800, from parts of Allegheny, Westmoreland and Lycoming Counties. It was named in honor of John Armstrong, who represented Pennsylvania in the Continental Congress and served as a major general during the Revolutionary War.
The County was named after John Armstrong, who served as a brigadier general and major general in the Revolutionary War.
Armstrong County is home to the City of Parker, an incorporated third-class city, which was an oil boom town with a population rumored to be approximately 20,000 in 1873, but now is the "Smallest City in America" with a population of just under 800. Parker is located in the extreme northwest portion of the county.
Iron was made in the Brady's Bend area of the county twenty years before there was a foundry in Pittsburgh doing so. Ford City is home to the plate-glass industry, as John Ford created the company which later became Pittsburgh Plate Glass.
Kittanning once boasted more millionnaires than anywhere else in Pennsylvania during the 1880s.
Leechburg was the first place in the United States to use natural gas for metallurgical purposes, in 1869. Natural gas was found while drilling for oil, and eventually introduced into the boilers and furnaces of Siberian Iron Works here.
Freeport, Leechburg and Apollo were communities built along the Pennsylvania Canal, which passed through on the Allegheny and Kiskiminetas rivers, at the southern border of the county.