Harrison Township is located in the extreme northeastern corner of Allegheny County, along the Allegheny River. It is part of the "Greater Tarentum" area - a small nexus of higher-density development surrounded by largely undeveloped rural land.
Although it is a township, in some ways Harrison is more "borough-like" in terms of its built form, with neighborhoods which run the gamut from urban to suburban. Close to the river is an ATI plant and
the neighborhood of Natrona, which was first built as a company town by the Pennsylvania Salt Manufacturing company in the 1850s. Built later were neighborhoods like
West Natrona (more streetcar suburb), and Natrona Heights proper (
ranch-era suburbia). Further north in the township, neighborhoods like Campton, Sylvan Park, and Birdville are found.
Harrison Township seems to lack a distinct walkable business district, but many of the older neighborhoods have individual businesses mixed in on residential streets. Along Freeport Road, there is an more typical suburban commercial strip, with a large strip mall in the center of the township, and a smaller strip mall with a Walmart Supercenter further to the north. Outside of the ATI plant and Allegheny Valley Hospital, there seem to be few employment concentrations left within township borders.