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Maryland and D.C.

Places We Protect

Rolling mountain ridges extend to the horizon blanketed in mist. In the foreground, leaves are just beginning to show fall color. In the background, heavy fog sits in a deep valley.
West Branch Wilderness Mist from the Susquehanna River viewed from a West Branch Wilderness overlook. © The Nature Conservancy/George C. Gress

With your help, The Nature Conservancy protects critical natural lands and life-giving waters in Maryland and DC.

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Public Preserves

Places We Protect

Bear Island Potomac Gorge

Over many millennia, a rare combination of natural forces carved the unique Potomac Gorge.

Places We Protect

Nassawango Creek Preserve

Nassawango Creek is one of the last pieces of true wilderness left on the East Coast.

Places We Protect

Finzel Swamp Preserve

A window into ice ages past, Finzel Swamp is located in a frost pocket, an area with characteristics of areas much further north.

Places We Protect

Cranesville Swamp

At Cranesville Swamp, the elements of wind, water, mountains and temperature have created a beautiful and rare landscape.

Other Places We Protect

  • A creek winds in a sinuous s-curve through a restoration site. The banks are covered in protective straw.

    Acopian Preserve

    Lancaster County—Closed to the Public. A patchwork of farms, forests and streams provide a combination of natural elements key to one of the state’s most important populations of federally endangered bog turtle. Learn More

  • Two canoes sit on the side of a river bank. A tall, tree-covered ridge rises in the background under a blue sky and white puffy clouds.

    Butternut Island

    Sullivan County, NY—Limited Access. Located in the Upper Delaware River, this uninhabited island boasts a floodplain forest that includes butternut trees, which are threatened by Japanese knotweed. 36 acres.

  • View looking from the interior of a cave out at two people standing at the cave's entrance.

    Hartman's Cave

    Limited Preserve Access—The cave is closed to the public. Hartman's Cave is located within Pennsylvania's Cherry Valley National Wildlife Refuge. Learn More

  • A bald eagle rests on a branch.

    Long Eddy

    Wayne County—Limited Access. Emerging from steep sandstone and shale slopes, Long Eddy’s wet cliffs nourish one of the only known populations of miner’s lettuce in the U.S. 121.6 acres. An additional 566 acres protected with a conservation easement.

  • Lush forest surrounds a wide wetland pond.

    Minsi Lake/Totts Gap

    Northampton Co.—Open to the Public. This collection of forestlands hugging part of the Kittatinny Ridge represents an important wildlife corridor and boasts the largest collections of vernal pools in PA. 2K acres. 150 acres open for public hunting.

  • A salamander with a long tail and red stripe running down its back sits nestled in a patch of moss.

    Mount Bethel Fens

    Northampton County— Closed to the Public. This complex of globally rare calcareous fens—a turn-of-the-century botanical wonder—will disappear if the delicate balance between water and chemical composition is disrupted.

  • A bush boasts pink flowers in bloom.

    Mount Holly Marsh

    Cumberland County—Open to the Public. TNC manages 200 acres of the preserve’s sensitive habitats and rare species in this mini-wilderness that encapsulates the surrounding South Mountain landscape.

  • A small toad sits on a long, thin leaf.

    Mountain Run Ponds

    Franklin & Cumberland Counties. During spring, the base of South Mountain awakes with seasonal vernal ponds that welcome frogs, toads, spring peepers and salamanders that emerge to breed. 10 acres.

  • Two small bats hang from the top of a cave.

    Richard O. Rowlands Preserve at Aitkin Cave

    Union County—Limited Access; cave is closed. Identified as a premier bat hibernacula in Pennsylvania dating back to the 1930s, Aitkin Cave harbors several species of bats and other unique cave-dwelling species. 43 acres. Learn More

  • A black-and-white butterfly rests in the middle of a pile of dry leaves.

    Westfall Ridge Prairie

    Juniata County—Limited Access. This limestone ridge is home to a globally rare rocky glade prairie community that once supported grazing animal herds, including bison. 32.25 acres. An additional 116 acres are protected under conservation easement.

Partnership in Action

Explore some of the places TNC has had a hand in protecting.

  • Water pools in a wide marshy area. Green plants and tall trees line the background and horizon.

    Bristol Marsh Preserve

    Open to the Public. TNC works with the Heritage Conservancy to protect rare plants native to the Delaware River; tidal marshes thrive here. Learn More

  • A wide stream flows between snow-covered banks. A fallen log rests at an angle with one end in the water.

    Cherry Valley National Wildlife Refuge

    Monroe and Northampton Counties—Open to the Public. A large part of TNC's work has focused on successfully establishing a national wildlife refuge with a consortium of local organizations and landowners. 20,000+ acres. Learn More

  • A person stands on a rock outcropping looking out at a valley landscape. Their view is obscured by a thick stand of trees.

    Kittatinny Ridge

    TNC is part of the Kittatinny Ridge Land Protection Partnership, a coalition of six local and regional land trusts working to protect 100,000 acres along the ridge by 2050. Learn More