Blue Mountain/Kittatinny Ridge

The Kittatinny Ridge, known as Blue Mountain across much of its length, is a long, narrow mountain ridge that runs for roughly 185 miles across Pennsylvania, extending from the Delaware River at the state's eastern border to the Mason-Dixon Line in the south. It is the first major landscape feature travelers encounter moving north or west out of the Philadelphia region, and it serves as the eastern gateway to Pennsylvania's Ridge and Valley province, the band of parallel folded mountains and farm valleys that defines the central part of the commonwealth.

Because it crosses so much of the state, the ridge is not a single park or preserve with one entrance, one address or one set of hours. It is a continuous landscape shared by about a dozen counties, a mix of state game lands, state forest and park tracts, county and municipal open space, land trust preserves, private woodlots and working farms at its base. The name Kittatinny is generally traced to a Lenape term understood to mean "endless mountain," a description that still fits the view from almost any high point along its spine.

Geography and Setting

Blue Mountain presents itself as a remarkably straight, even-crested wall of forested rock, rising several hundred to roughly a thousand feet above the valley floor. Its resistant sandstone and quartzite caprock is the reason it has survived erosion while the softer shale and limestone valleys on either side wore down around it. Where rivers and creeks cut through the ridge, they form the water gaps that have long shaped travel and settlement in Pennsylvania, including the Delaware Water Gap, Lehigh Gap, Schuylkill Gap, Swatara Gap and the Susquehanna crossing near Duncannon.

The ridge forms the scenic backdrop for communities in roughly twelve counties, among them Monroe, Northampton, Lehigh, Carbon, Berks, Schuylkill, Lebanon, Dauphin, Perry, Cumberland, Franklin and Adams. For many residents of the Lehigh Valley, the Susquehanna Valley and south central Pennsylvania, it is the horizon line they see every day, and for visitors it is the first real mountain country within an easy drive of Philadelphia, Harrisburg, Allentown, Reading and the greater New York and Baltimore metropolitan areas.

The Appalachian Trail

The Appalachian National Scenic Trail follows the crest of the Kittatinny Ridge for a substantial portion of its route through Pennsylvania. Thru-hikers working their way between Georgia and Maine know this stretch for its rocky footing, its long open ledges and its sweeping views over farmland and small towns. Day hikers and weekend backpackers use the same corridor, reaching it from road crossings at the water gaps and from side trails maintained by volunteer hiking clubs.

Popular access points and viewpoints along the ridge include outcrops and knobs that look out over the valleys on both sides, with trail shelters and campsites spaced along the route. Footing is often uneven and rocky, so sturdy boots, water and a map are sensible for any trip of more than a short walk. Many segments can be hiked as out and back routes from parking areas at gaps, which makes the ridge approachable for casual visitors as well as experienced backpackers.

A Major Raptor Migration Corridor

The Kittatinny Ridge is internationally recognized among birders as one of the premier raptor migration corridors in the northeastern United States and one of the leading hawk watching regions anywhere. Each autumn, tens of thousands of hawks, eagles and falcons ride the updrafts and thermals generated along the ridge as they travel south, concentrating birds into a narrow aerial highway that observers can watch from fixed lookouts. Smaller numbers follow the ridgeline northward in spring.

Species regularly recorded include Broad-winged Hawks, which can pass in large swirling flocks known as kettles, along with Sharp-shinned and Cooper's Hawks, Red-tailed and Red-shouldered Hawks, Northern Harriers, Ospreys, Bald and Golden Eagles, American Kestrels, Merlins and Peregrine Falcons. Counts at long running lookouts on the ridge have contributed decades of data used by researchers tracking raptor population trends.

Raptors are not the only travelers. Ruby-throated Hummingbirds and Monarch Butterflies also move along the ridge during migration, and songbirds pass through the forest canopy in large numbers during spring and fall. In recognition of this concentration of migratory activity and the breeding habitat the ridge provides, the Kittatinny has been designated a Global Important Bird Area.

Wildlife and Habitat

Beyond migratory birds, the ridge supports a broad range of wildlife typical of Pennsylvania's forested uplands, including white-tailed deer, black bear, bobcat, fox, turkey, grouse, timber rattlesnake and numerous amphibians and forest songbirds. Because the ridge is largely unbroken for so many miles, it functions as a continuous habitat corridor that allows wildlife to move across an otherwise developed and fragmented landscape.

The ridge also plays an important role in water quality. Although anglers rarely fish on the mountain itself, nearly every high quality coldwater stream in the surrounding region begins on its slopes. Forest cover on the ridge filters rainfall, moderates stream temperatures and feeds the headwaters that support trout fisheries and public drinking water supplies in the valleys below.

Recreation Through the Seasons

• Hiking and backpacking on the Appalachian Trail and connecting side trails
• Hawk watching and birdwatching, with peak raptor flights from late August through November
• Landscape and wildlife photography, particularly during autumn foliage
• Hunting on the many State Game Lands tracts that follow the ridge, as well as on private land with permission
• Scenic driving through the water gaps and along valley roads with ridge views
• Nature study, environmental education programs and volunteer trail and habitat work

Autumn draws the heaviest visitation, when foliage color and migration peak at the same time. Spring and summer bring wildflowers, breeding birds and cooler ridgetop temperatures, while winter offers long views through bare trees and the chance to see wintering eagles and other raptors.

Conservation and Visiting

Protecting the Kittatinny Ridge is an ongoing effort involving state agencies, conservancies, land trusts, county planners, municipalities and conservation organizations that coordinate land protection, trail stewardship, habitat management and public education along the corridor. Priorities include keeping large forest blocks intact, protecting headwater streams and maintaining the viewsheds that give the ridge its character.

Visitors should note that the ridge spans many separate properties with different rules. Hunting seasons apply on State Game Lands, parking is usually limited to designated lots at road crossings and trailheads, and cell service can be unreliable on the mountain. Carrying out all trash, staying on established trails and respecting posted private property boundaries help keep access open. With hundreds of thousands of people using the ridge each year, that shared care is a large part of what keeps this landscape available for the next season of hikers, hunters, birders and sightseers.