Nestled just below the ridgeline that separates New Hampshire from Quebec, Fourth Connecticut Lake marks the humble beginnings of New England's longest river. More than 400 miles long, the Connecticut River is also the largest watershed in the region, draining nearly 12,000 square miles of New Hampshire, Vermont, Massachusetts, and Connecticut, where it enters the ocean at Long Island Sound.
Fourth Connecticut Lake Preserve symbolizes the importance of the Connecticut River watershed while protecting important boreal habitat. At 78.1 acres, the preserve is surrounded on the U.S. side by an additional 4,900 acres protected by a conservation easement held by The Nature Conservancy and owned by the state of New Hampshire (part of the Connecticut Lakes Headwaters Natural Area).
The forest in the preserve is thick with balsam fir, and peppered with red spruce, paper birch, and mountain ash, making it ideal habitat for boreal birds like the northern three-toed woodpecker and spruce grouse, as well as woodland wildflowers like wood sorrel, bunchberry, creeping snowberry, and lady’s slipper. At 2.5 acres in size, the lake itself is considered a northern acidic mountain tarn, a small pond created by glacial action during the last ice age. Though shallow (it has a maximum depth of 5 feet) the pond does not completely freeze in winter and supports a small year-round fish population, river otter, and beaver.