Allegheny

Allegheny or Alleghany may refer to:

Geologic and geographic features

Allegheny River, in Pennsylvania and New York
Allegheny Mountains, part of the Appalachian Mountain Range in West Virginia, Pennsylvania, Maryland and Virginia
- Allegheny Mountain (Pennsylvania), major mountain ridge in the northern part of the Allegheny Mountains
- Little Allegheny Mountain, in Pennsylvania and Maryland, see list of mountains of the Alleghenies
- Allegheny Mountain (West Virginia – Virginia), major mountain ridge in the southern part of the Allegheny Mountains
- Back Allegheny Mountain, in West Virginia
Allegheny Plateau, which terminates in the east at the Allegheny Mountains
Allegheny Front, the escarpment delineating the eastern edge of the Allegheny Plateau and Mountains, separating them from the lower Ridge and Valley Appalachians
Allegheny Formation, a mapped bedrock unit of West Virginia, Maryland and Pennsylvania

Allegheny Mountain Tunnel, a vehicular tunnel on the Pennsylvania Turnpike
Allegheny Reservoir, a reservoir on the Allegheny River
Allegheny River Tunnel, a light rail tunnel under the Allegheny River in Pittsburgh
Allegheny Observatory, at the University of Pittsburgh

Allegheny Railroad, a railroad operating in northwestern Pennsylvania (1985–92)
Allegheny Valley Railroad, a railroad operating in Western Pennsylvania since 1992
Allegheny Valley Street Railway, an electric rail line operating along the Allegheny River (1906–37)
Allegheny (PAT station), a station on the Pittsburgh Light Rail system
2-6-6-6, a locomotive of the "Allegheny class"
Allegheny (train), a St. Louis-Pittsburgh passenger train operated by the Pennsylvania Railroad

Alleghany Corp., a railroad holding company
Allegheny Airlines, a forerunner of US Airways
Allegheny College, in Meadville, Pennsylvania
Allegheny Energy, a public utility (including its subsidiary Allegheny Power)
Allegheny Foundation, a charitable organization focused on Western Pennsylvania
Allegheny Mountain Radio, a network of radio stations in West Virginia and Virginia
Allegheny Technologies, a specialty metals company
Allegheny (titular see), a Roman Catholic titular see
Pittsburgh Allegheny (International Association), a nineteenth century minor league baseball team that, at times, played at under the name "Allegheny"

Pachysandra procumbens or Allegheny pachysandra, a plant in the box family
Allegheny woodrat, a species of pack rat in the eastern United States
Allegheny Mountain dusky salamander, a species of the eastern United States and Canada
Allegheny mound ant, a species of the eastern United States and Canada
"Allegheny alligator", nickname for the hellbender
Allegheny chinquapin (Castanea pumila), a species of chestnut