Places We Protect

Thompson Pond Preserve

New York

A deep blue pond with lily pads along the edge and grasses and trees on the bank.
Thompson Pond Preserve A sunny day on Thompson Pond in New York © Marcela Medina/TNC

Discover an ancient pond basin at the foot of this mountain preserve.



At the foot of Stissing Mountain lies the ancient Thompson Pond Basin, which formed nearly 15,000 years ago when a melting ice chunk created a depression or kettle. Over time, the kettle divided into three interconnected water bodies, including Thompson Pond, which forms the headwaters of a major tributary of the Hudson River. The basin's pond, cattail marsh, swamp and upland forest support a wondrously diverse array of wildlife.

Before you visit, please download a preserve map.



Closed to the public on April 13th and 14th, 2023 for staff work days.


Open year-round from dawn until dusk.


530 acres

Explore our work in New York


  • The preserve is open dawn to dusk for passive recreational and educational uses, such as cross-country skiing, hiking and bird study. 

  • Plants: More than 245 species of land plants and 142 wetland plant species have been identified at the preserve. Around the wetlands, you can find pipewort, round-leaved sundew, marsh St. Johnswort, a cattail community, and ferns and wildflowers that grow in calcareous and acidic soils. Woodlands feature oaks, sugar maples, ash, hemlock, and hickory.

    Wildlife: Migratory birds, including ducks and warblers, pass through here in great numbers, and this is one of the best spots in the region for observing water birds such as rails. Red-tailed hawks nest in the area and golden eagles soar over open fields and near the peak of Stissing Mountain.

  • There are several trails around the pond, with a newly constructed bog bridge along the yellow trail that makes it possible for visitors to complete the full loop. For stunning views of the area, take the steep trail leading to a historic fire tower on the top of Stissing Mountain. Explore our Thompson Pond Trail Map for further details. 

    • Please note: The trail around Thompson Pond travels close to the water’s edge; visitors might get their feet wet. Please wear appropriate footwear.


A new wheelchair-accessible trail was recently installed at Thompson Pond Preserve. The fine crushed stone trail is approximately a half mile and concludes at a viewing point overlooking Thompson Pond. The viewing area is a perfect spot to watch birds and wildlife.

As you arrive at Thompson Pond Preserve, there are two handicap parking spaces and one van accessible space in the parking lot. Access our trail map to explore more about this location.

Closeup view of golden marsh grasses.
Thompson Pond Wetlands This preserve is home to 387 different plant species. © Carl Heilman

Why We Selected This Site

Thompson Pond was designated a National Natural Landmark by the U.S. Department of the Interior in 1973. It is considered an excellent example of a calcareous (or limy) wetland that abounds with a variety of wildlife. The Nature Conservancy seeks to preserve its 387 plant species, 162 bird species and 27 mammal species.

What We Do Here

As development threatens to alter the bucolic character of the region, The Nature Conservancy is working to promote the continued protection of the area's open space and other local natural resources. Ecological researchers and natural history clubs are encouraged to utilize Thompson Pond Preserve for educational and research activities.