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About the Gunks

What are the Gunks?


The Gunks are located west of the Hudson River in New York State. The official name of the ridge is the Shawangunk Mountains. This ridge runs north-south from vicinity of Rosendale in the north, and Ellenville in the south.  Most of the permitted rock climbing is in the Mohonk Preserve, which is west of the town of New Paltz.

Autumn view of the Trapps Cliff, the main cliff band at the Gunks, part of the Mohonk Preserve

Trapps Cliff – Gunks

There are multiple entities which own the ridge, as well as numerous private landowners. There are 4 major entities that own much of the ridge. All of them require an entry fee to use the land.

  • From the south, Sam’s Point Preserve is owned by the Open Space Institute and managed by the Nature Conservancy. It is a beautiful place to hike, known for its once-commercial Ice Caves, dwarf pitch pine forest and Lake Maratanza.  Alas, no climbing is permitted there.
  • Beautiful Lake Minnewaska, ringed by cliffs.

    Lake Minnewaska

    Minnewaska Lake State Park Preserve is a state-owned park with more than 21,000 acres of park. It has two major lakes, Lake Minnewaska, and Lake Awosting. This park is very popular with hikers, mountain bicyclers and cross-country skiiers. Although there are miles of climbable rock here, only one small section is open to rock climbing, Peter’s Kill. Access to the top of Millbrook cliff is from Minnewaska Lake State Park Preserve.

  • The Mohonk Preserve owns most of the cliffs people think of as “The Gunks” because they allow climbing. The Near Trapps and the Trapps are the most popular cliffs for climbing, hosting hundreds of routes. Route 44/55 runs between these two cliffs. Two cliffs which are not documented in any guidebook, Lost City and Bonticou, are also popular for rock climbing and are less crowded. The Preserve has over 7,000 acres and is very popular with hikers, mountain bicyclers and cross-country skiiers.

    View of the beautiful Mohonk Mountain House Resort on Lake Mohonk.

    Mohonk Mountain House Resort

  • The Mohonk Mountain House is a private commercial resort hotel, founded in 1869, and one of the last surviving great Catskill resorts. It is a sight to behold. The iconic Skytop cliff, with its stone tower on top, is a landmark of New Paltz and the Shawangunk Ridge. Climbing is restricted to guests who use their approved guide service. You must climb with their guides to use the cliff. As you can expect with a resort of this stature, it is very expensive. Day guests pay significant day pass fees and cannot park near the hotel, although shuttle buses are offered. Guests of the nearby Mohonk Preserve can hike/bike/ski into the Mohonk Mountain House grounds from the Mohonk Preserve using their Mohonk Preserve day pass, but cannot park near the hotel, enter the hotel or climb.

Geology of the Shawangunk Ridge

The Shawangunk Conglomerate extends from High Point, New Jersey and across the Deleware Water Gap into Pennsylvania (called the Kittatinnny range), as well as south to West Virginia (North Fork Mountain and Seneca Rocks) to Alabama. Only near New Paltz and Seneca Rocks are the rocks durable enough for a major rock climbing area.

The Shawangunk Mountain’s bedrock consists of two formations: the Shawangunk Conglomerate, which makes up the cliffs so popular with rock climbers, and the Martinsburg Formation, which is mostly shale that you may see below the conglomerate. The shale was formed when layers of clay and silt accumulated at the bottom of a sea about 465 million years ago. These sediments hardened into shale. The sea water disappeared when the region was uplifted.

About 420 million years ago, a shallow sea spread across a level landscape of eroded shale. Rivers carried pebbles and quartz sand grains which were laid down as gravel layers. As this gravel was buried under piles of younger accumlations of sediment, the weight of the overlying sediments transformed the gravel layer into Shawangunk Conglomerate. This conglomerate has a natural “cement” of quartz which holds the quartz particles together, to form one of the hardest and most durable of rocks. The Shawangunk Conglomerate is very hard and resistant to weathering; whereas the underlying shale erodes relatively easily. A good place to see the dark crumbly shale formation is on Route 44/55 across the street from the scenic overlook.

A close up view of the Shawangunk Conglomerate rock that makes up the Gunks

Shawangunk Conglomerate of the Gunks, close-up

About 350 million years ago, a collision between the African and North American tectonic plates of the earth’s crust created an uplift that deformed and raised the Shawangunk Mountains, causing extensive folding and faulting.

Millions of years of erosion have worn down the upper layers of limestones and shales which dissolved and crumbled more easily than the quartz conglomerate, leaving the Shawangunk Conglomerate exposed as the top layer. When the glaciers came through during the ice ages, the ice ground across the ridge, removing the ancient soils, exposing the bedrock surfaces, carving grooves and striations on the bedrock by pebbles and boulders imbedded in the overriding ice, and leaving occasional erratics – boulders left as the ice melted away. Once the rocks age and become hard and brittle, crustal movements can cause them to break along cracks or joints. Water freezing within these joints over time creates a wedging action that creates blocks that move apart and sometimes fall off the cliff. These cracks enable the plethora of excellent climbing routes on the cliff face.

Drawing of the cross section of the Gunks cliff, showing the geology.

Cross section of the Trapps Ridge, Gunks


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