Blue Mountain, Blue Mountain Ridge, or the Blue Mountains of Pennsylvania is a ridge of the Appalachian Mountains in eastern Pennsylvania. Forming the southern and eastern edge of the Ridge-and-Valley Appalachians physiographic province in Pennsylvania, Blue Mountain extends 150 mi from the Delaware Water Gap on the New Jersey border in the east to Big Gap in Franklin County in south-central Pennsylvania at its southwestern end. Views of Blue Mountain dominate the southern tier of most eastern and central Pennsylvania counties, providing an ever-visible backdrop cutting across the northern or western horizon. Most transport corridors and road beds piercing the barrier necessarily pass through large water gaps, including (west to east) the Susquehanna, Schuylkill, Lehigh and Delaware River valleys or wind gaps, low gaps in the ridge caused by ancient watercourses. The barrier ridge forms a distinct boundary between a number of Pennsylvania's geographical and cultural regions. To the south of the Susquehanna River gap in the south-central part of the state is the Cumberland Valley, part of the Great Appalachian Valley; to its northwest side are the southern reaches of the Susquehanna Valley with picturesque streams channeling travel corridors deep into and over the central and western mountains and valleys—the heartland interior counties of Pennsylvania; along the Main Branch Susquehanna, the valleys also lead into the Coal Region of northeast Pennsylvania, the Wyoming Valley, and the distant Poconos. To the south of Blue Mountain lies the Capital Region of Harrisburg and nearby communities, the rich farming country of the Lebanon Valley and Pennsylvania Dutch Country of York and Lancaster counties, the lower half of the Lehigh Valley, and the lower Delaware Valley, both of which extend north through water gaps beyond the ridgeline. Blue Mountain School District, which is named after the mountain range, is located just off PA Route 61 in Schuylkill Haven, Pennsylvania.

Geography

The ridge of Blue Mountain runs for 150 mi through Pennsylvania, reaching an elevation of 2270 ft above sea level just north of the Pennsylvania Turnpike, near the borough of Newburg. Most of the ridgecrest, however, only reaches between 1400 and 1700 ft in elevation. The mountain's width varies from 1 to 3 mi. The southwestern end of the mountain is at Big Gap, west of Shippensburg. The mountain ridge continues to the southwest toward Maryland as Broad Mountain. The northeastern end of the mountain is at the Delaware Water Gap on the New Jersey border. Mount Minsi, elevation 1461 ft, forms the promontory overlooking the Delaware River. The ridge of Blue Mountain continues northeast into New Jersey as Kittatinny Mountain. Blue Mountain marks the boundary between the Great Appalachian Valley and the main Ridge-and-Valley Appalachians.

Water gaps

Four of Pennsylvania's major rivers cut through Blue Mountain in water gaps:

Pennsylvania Turnpike

The Pennsylvania Turnpike system passes through Blue Mountain at two points:

Blue Mountain attractions in Pennsylvania