Pennsylvania Geography & Climate

Pennsylvania is about 300 miles wide and the Appalachian ridges run diagonally across the middle of it, which is why crossing the state takes longer than the map suggests.

The southeast is fertile piedmont farmland and coastal plain around Philadelphia, on the Delaware River. The northeast holds the Poconos and the anthracite coalfields — the only significant hard-coal deposits in the country.

West of the ridges the land becomes the Allegheny Plateau, cut by deep valleys. Pittsburgh sits where the Allegheny and Monongahela rivers join to form the Ohio River, and the terrain is steep enough that the city runs two funicular inclines and more bridges than any other city in the world.

The far northwest touches Lake Erie, giving the state a short but genuine Great Lakes shoreline and the vineyards that come with it.

Summers are warm to hot and humid, most oppressive in the southeast around Philadelphia and noticeably cooler in the mountains.

Winters are cold across the state with real snow. The northwest near Lake Erie gets lake-effect snow in serious quantities, and the mountain roads need genuine winter tyres.

Autumn is the state's best season — long, dry and cool, with foliage moving from north to south through October.

Spring is short and wet. Remnants of Atlantic hurricanes occasionally bring heavy rain and river flooding in late summer.