Map of the Allegheny plateau.
Allegheny Plateau is a large dissected plateau area in western and
York, northern and western Pennsylvania, northern West Virginia, and eastern Ohio.
The gray line divides the glaciated (northern) and unglaciated
(southern) sections of the plateau.
is divided into the unglaciated Allegheny Plateau
and the glaciated Allegheny
plateau extends southward into western West Virginia, eastern Kentucky and Tennessee where it is instead called the Cumberland Plateau.
The plateau terminates in the east at the Allegheny Mountains
, which are the
highest ridges just west of the Allegheny Front
. The front extends from
central Pennsylvania into eastern West Virginia.
plateau is bordered on the west by glacial till plains in the
north, generally north of the Ohio River,
and the Bluegrass
region in the south, generally south of the Ohio
Elevations vary greatly. In the glaciated Allegheny Plateau, relief
may only reach one hundred feet or less. In the unglaciated
Allegheny Plateau in southeastern Ohio and westernmost West
Virginia, relief is typically in the range of two hundred to four
hundred feet. Absolute highest elevations in this area are often in
the range of . By the Allegheny Front, however, elevations may
reach well over , with relief of up to .
One of the
more notable geologic areas within the Allegheny Plateau is the
Hocking Hills region of
Geology and physiography
Allegheny Plateau is a physiographic section of
the larger Appalachian
Plateau province, which in turn is part of the larger
Appalachian physiographic division.