The Delaware Water Gap National Recreation Area
(Excerpts from www.nps.gov/DEWA)
The park preserves 40 miles of the middle Delaware River and almost 70,000 acres of land along the river's New Jersey and Pennsylvania shores. At the south end of the park, the river cuts eastward through the Appalachian Mountains at the scenic Delaware Water Gap. A one-day auto tour of the park can include waterfalls, rural scenery, and historic Millbrook Village. Visitors can also canoe, hike, camp, swim, picnic, bicycle, cross-country ski, and horseback ride. Fishing and hunting are permitted in season with state licenses.
The Gap
The Delaware Water Gap is a geological testament to the power of flowing water. It is bounded by Mt. Minsi in Pennsylvania and Mt. Tammany in New Jersey. Once touted as a scenic Wonder of the World, it is an impressive site when motoring through on Interstate 80 or viewed from the overlooks along Rt. 611 on the Pennsylvania side.
The Ridge
Before the Gap formed. Mt. Minsi and Mt. Tammany formed one continuous ridge -- the Kittatinny Ridge, along which the Appalachian Trail runs through the park today. Here at the Gap, this ridge is composed of two different sedimentary rock formations: the Shawangunk Formation, and the Bloomsburg Redbeds.
The Rocks
The Shawangunk Formation is the older of the two and forms the bulk of the mountain. It is composed of three layers -- or members. The top and bottom members are largely sandstone, with little shale. The middle layer has a mix of weaker shales and sandstones, and this is where trees grow.
The Bloomsburg Redbeds are more recent and cover the top of the mountains. They consist of layer upon layer of sand and mud that later became stones and shales of the formation.
The Mountains
Although they now tilt upwards at a precarious angle, the Shawangunk and Bloomsburg Formations were laid down horizontally. When the African Plate collided with the North American Plate 250 million years ago, the force of the collision bent the rock layers into folds, forming the Appalachian Mountain chain. Erosion has removed the rock from what is now the Water Gap.
The Work of Water
There are several explanations of how the Water Gap formed, but essentially, erosion has removed the rock from what is now the Water Gap. Headwater Erosion (and stream-capturing) explains that the folding of the rocks layers resulted in a weakened spot in the ridge. Creeks flowing down the mountain eventually slowly eroded their way back through the ridge until they cut the whole way through and "captured" a river on the other side of the ridge. Superposition explains that creeks eroded an ever deepening channel; the folding or weakening of the rock is not involved.
Ice Comes and Goes
Glaciers have come to this valley and melted away several times over millions of years, the last (Wisconsin) glaciations having melted away 20,000 years ago. While glaciers likely carried away rock from the slopes, the Water Gap was already by the time that the glaciers advanced. There are glacial erratics (boulders) and till deposits in the valleys and on the mountains, and glacial striate (scratches) on the walls of the Gap itself.
A Work in Progress
Though in the human frame of time, the Gap looks "finished," erosion is ongoing. Even if you don't know one rock from another, or one geologic era from another, take a moment to ponder the power of water over immense periods of time -- water is still forming the Gap, drop by drop, as you watch the river flow by today. On the Pennsylvania side, streams tumble off the Pocono plateau and rush through dark hemlock groves to the river. Watch the watershed in action at Dingmans Falls, Raymondskill, or Childs Park.
Hiking the Endless Mountain
You are in the footsteps of two centuries of hikers as you climb the gateposts of the gap, Mt. Minsi PA and Mt. Tammany NJ and emerge atop the "endless mountain" — Kittatinny Ridge. You can hike 27 miles of the Appalachian Trail within the park. Most hikers want to climb Mt. Tammany in New Jersey, but the best view of Tammany is from the top of the other gatepost of the Gap, Mt. Minsi in Pennsylvania. From Lake Lenape in the village of Delaware Water Gap to the top of Mt Minsi is about 2 miles. Day hikers can return from the top via the
Mt Minsi Fire Road for a vigorous 4-mile loop. Less strenuous hikes are available to the first overlook on the Appalachian Trail, along the creek bed down to Resort Point overlook, around Lake Lenape, and through the old roadways around Lake Lettini. Most hikers want to climb Mt. Tammany in New Jersey. From Dunnfield Creek parking area (Worthington State Forest) to the top
of Mt. Tammany via the Red Dot Trail is a steep and rocky 1.5 mile climb. From Dunnfield Creek parking area (Worthington State Forest) to the top
of Mt. Tammany via the Blue Blazed Trail is a more gradual 2.5 mile climb, most of it on wide trails and old roadbeds. The Red Dot and the Blue Blazed (or Blue Dot) trails join at the top of Mt. Tammany to form a 4-mile loop. Also atop Mt. Tammany is the
Mt Tammany Fire Road, which runs along the ridge to meet the Turquoise Trail to Sunfish Pond. This is one way to hike both Mt. Tammany and Sunfish Pond without backtracking.
TRAIL SUGGESTIONS: (See Hiking Map) Hikes from 2 to 6 hours in length Mt Minsi at the Gap (loop hike: Hikes 1 and 3)
McDade Trail: Hialeah to Turn Farm (5 miles each way, climbs slowly but steadily northbound)
Pocono Environmental Education Center (PEEC) PA (a variety of trails open to all park visitors)
History Hikes and StrollsMcDade Trail I: Hialeah to Turn Farm
Lime Kilns near McDade Trail and Zion Church
McDade Trail II: Milford Beach to Pitman Orchard
- (Fairly) Flat and Easy Trails
- about 2 miles round-trip
- little or gradual ascent; no scrambling
- flat trail surface and fairly good footing
Most sections of McDade Trail
Toms Creek Trail
The Appalachian Trail from Totts Gap to the view of Mt. Tammany
Wheelchair-Accessible TrailsThe boardwalk trail at Dingmans Falls.
Click here for hiking maps(
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