Places We Protect

Sideling Hill Creek

Maryland / DC

A wide, shallow creek curves between two heavily forested banks. The trees show autumn colors of red and gold. The water ripples over small rocks in the center of the creek.
Sideling Hill Creek One of Maryland's healthiest stream systems. © Harold E. Malde

Explore one of Maryland's healthiest stream systems



Originating from the southwestern mountains of Pennsylvania, Sideling Hill Creek tumbles its way down the steep, forested, shale cliffs of western Maryland before it finally spills into the Potomac River. 

The Sideling Hill watershed is about 80% forest cover and is incredibly intact.  The area is sparsely populated, and this isolation has allowed Sideling Hill Creek to have supremely high water quality and healthy aquatic communities. 

The preserve has several trails so visitors can explore the variety of species and natural communities that exist at Sideling Hill Creek.  



    • The world's healthiest population of the globally rare aquatic wildflower, harperella.
    • Twelve rare, endemic (occurring only on the shale barrens and nowhere else) plants including the nationally endangered evening primrose, shale ragwort, and Kate's mountain clover.


    • Olympian marble butterfly, green floater mussel, tiger beetle.
    • Wild turkey, hawks, and bobcat.
  • Passive recreation such as walking, bird watching and photography is welcomed. To protect the health of our preserves for generations to come, and to ensure the safety of all visitors, the following activities are not allowed:

    • Picking flowers, mushrooms, etc.; removing rocks or other parts of the landscape
    • Smoking
    • Camping, fires or cookouts
    • Driving motorized vehicles, including ATVs, except on designated access roads
    • Biking
    • Fishing, trapping or hunting, except as otherwise posted
    • Bringing dogs onto the preserve
    • Horseback riding
    • Feeding wildlife
    • Releasing animals or introducing plants
    • Disposing of trash or other waste, including biodegradable materials

    In addition, in order to minimize the impact visitors have on the preserve, we ask that you please:

    • Use trails.
    • Avoid walking in wet, boggy areas.
    • Inspect pant legs and shoes to remove seeds before entering and when leaving the preserve. Failure to do so could introduce unwanted weeds to new locations.
    • If you flush a ground nesting bird—stop and avoid walking near the nest area.
    • Observe all posted signs.
    • Please do not remove stakes, signs, flagging, tape or other objects—they might be part of a research project.
    • Please do not trespass on private property adjacent to the preserve.

Audio Tour

Sideling Hill Controlled Burn

A 55-acre burn conducted in 2019 aimed to help a variety of fire-adapted native tree and plant species. The burn also offered a unique opportunity to connect the local community to our fire work, giving local residents and visitors a better look at this critically important conservation practice. 

Working with Fire
A man in yellow fire gear points to a map hanging on a wall during a pre-burn briefing. Four people stand behind him listening to the briefing.
Three women wearing yellow fire gear stand together.
Two girls lean their elbows on a table bending over a map to closely examine it.
Smoke from a controlled burn rises above a green forested hill as cars drive by on the interstate highway that runs along the edge of the forest.
Five adults gather at an outdoor table and lean in to look at tree rings and pamphlets that are on the tabletop.

Explore Nature

Need more nature? Visit some of TNC's other preserves.

Stay in Touch

Subscribe to Nature News, our monthly e-newsletter. Get the latest news and updates about our conservation efforts locally and around the world, delivered straight to your inbox.

Find More Places We Protect

The Nature Conservancy owns nearly 1,500 preserves covering more than 2.5 million acres across all 50 states. These lands protect wildlife and natural systems, serve as living laboratories for innovative science and connect people to the natural world.

See the Complete Map