There are eight National Natural Landmarks in Connecticut. They represent the geological and ecological history of Connecticut, including glacial features such as bogs, old growth forests and swamps. There are also well preserved dinosaur tracks,
Connecticut National Natural Landmarks (clickable map)
| Name | Image | Date | Location | County | Ownership | Description |
|---|---|---|---|---|---|---|
| Bartholomew's Cobble | .JPG)
|
October 1971 | Canaan 42°03′26″N 73°21′03″W / 42.057222°N 73.350833°W | Litchfield | private | Open space preserve, agricultural preserve, and bio-reserve primarily located in Ashley Falls, Massachusetts and edging into Canaan, Connecticut. The preserve contains over 800 plant species including North America's greatest diversity of ferns. It is open to the public with hiking trails and a visitors center. |
| Beckley Bog | 
|
May 1977 | Norfolk 41°58′08″N 73°09′44″W / 41.96889°N 73.16222°W | Litchfield | private | The southernmost Sphagnum-heath-black spruce bog in New England. Purchased by the Nature Conservancy in 1956. |
| Bingham Pond Bog | May 1973 | Salisbury 42°01′13″N 73°27′59″W / 42.02028°N 73.46639°W | Litchfield | private | A rare undisturbed northern black spruce bog, which is missing the more common Sphagnum moss. | |
| Cathedral Pines | 
|
May 1982 | Cornwall 41°50′10″N 73°19′31″W / 41.836044°N 73.325163°W | Litchfield | private (The Nature Conservancy) | A large tract of old-growth white pine and hemlock forest owned by the Nature Conservancy which was mostly destroyed by tornadoes in 1989. |
| Chester Cedar Swamp | 
|
May 1973 | Chester 41°23′15″N 72°29′20″W / 41.387499°N 72.488995°W | Middlesex | mixed- state, municipal | Known for its Atlantic white cedar swamp within the Cockaponset State Forest. |
| Dinosaur Trackway | _-_prints.JPG)
|
April 1968 | Rocky Hill 41°39′07″N 72°39′25″W / 41.651944°N 72.656944°W | Hartford | state | One of the largest dinosaur track sites in North America, with a fine display of early Jurassic fossil tracks in sandstone from about 200 million years ago. |
| McLean Game Refuge Natural Areas | 
|
November 1973 | Granby 41°55′14″N 72°47′19″W / 41.920545°N 72.788544°W | Hartford | private | 4,400 acres (1,800 ha) forest in multiple tracts has a very diverse group of species as well as evidence of glacial activity. |
| Pachaug-Great Meadow Swamp | 
|
May 1973 | Voluntown 41°35′57″N 71°52′41″W / 41.599167°N 71.878056°W | New London | mixed- state, private | Known for the Atlantic white cedar swamp inside the Pachaug State Forest. Includes sections of the Pachaug River and the Great Meadow Brook. |