Member Login. The following was included in TCTA's 2015-16 Survival Guide, the ultimate reference tool for Texas educators, and is current as of September 2015 but is subject to change.
The Allegheny Mountains run diagonally from the southwest to the northeast with piedmont and coastal plains in the southeast triangle. The Allegheny Front, as it's called, cuts a diagonal line across the state. In the northwest, the plateau falls to the Lake Erie lowlands and, finally, Lake Erie. ( Pennsylvania Close-up)
1 West Virginia - Pennsylvania's southwestern neighbor is the only state in the USA to lie completely within a mountain range (in this case, the Appalachians).  Ohio - The Buckeye State is Pennsylvania's western neighbor, offering the Rock and Roll Hall of Fame in Cleveland and the Pro Football Hall of Fame in Canton.