Brackenridge is a borough in Allegheny County in the U.S. state of Pennsylvania, along the Allegheny River. It is part of the Pittsburgh Metro Area. The town is named for Henry Marie Brackenridge. The borough once had glass factories. An Allegheny Technologies steel mill, Allegheny Ludlum Brackenridge Works, plays a prominent role in the community, although most of the facility is located in Harrison Township. The population stood at 3,421 in 1910 and at 6,400 in 1940.