Gamlin Crystal Spring


The Gamlin Crystal Spring Conservation Area is bisected into west and east parcels by Old Dunstable Rd. Parking/trailheads for the west and east parcels are in different locations.

Parking to access the west parcel, including the Indian Rock Trail and Boulders Trail, is located on Old Dunstable Road. Take Lowell Rd. (Rt. 40) to Old Dunstable Rd. Proceed north on Old Dunstable Rd., passing the intersection with Bridge Street after 1.25 miles, then continuing for another 0.25 miles on Old Dunstable Rd. The trail head and parking are on your left, across from a wooden mailbox.

Parking to access the east parcel and its trail, the Gamlin Esker Trail, is at the very end of Cow Pond Brook Rd., past the Town Transfer Station, where there is a road gate.


Trails Daily dawn to dusk


The Gamlin Crystal Spring property was donated by Robert and Frances Gamlin to the Groton Conservation Trust in 2005. Prior to the donation, three generations of the Gamlin family had worked the land for nearly 100 years, primarily in forestry, agriculture, and operation of a Christmas tree farm. At the time of the land donation, Mr. Gamlin pointed out the stump still remaining in 2005 of a giant chestnut tree that his father had harvested in the 1923


The Gamlin Crystal Spring Conservation Area is a Groton standout for its striking diversity of forest types, plant/animal life, and geology such as streams, eskers, cliffs, and giant boulders.

The wooded west parcel is accessed by the Indian Rock Trail and the Boulders Trail. The Indian Rock Trail is named for a high rock promontory called Indian Rock by the generations of Gamlin children who scrambled to the top for the commanding views, just as they imagined Native Americans had done centuries before them. And speaking of multi-generational history, porcupines have lived in a den below Indian Rock for decades. The west parcel features hardwood trees in the uplands and hemlocks along a brook that flows through the parcel. The brook and its wetlands are home to beavers, turtles, herons, and wood ducks.

The east parcel, also wooded, is accessed by taking the Red Line Path to Bridge St. Extension (a cart path), then the Gamlin Esker Trail. The east parcel features a long, high esker. Hikers traversing the esker are afforded fine views of Cow Pond Brook flowing below. The east parcel also has a prominent wetland area, with constant beaver activity. Deer are seen on the esker, and the esker is habitat for nesting turtles and playful otters. In a remote area explored by few, a small spring feeds Cow Pond Brook on its west bank, that spring lending its name to this wonderful conservation area.

The Gamlin Crystal Spring Conservation Area and abutting protected properties together create the largest contiguous protected area in Groton of approximately 1,400 acres. The Gamlin Crystal Spring parcels abut over 700 acres protected by the New England Forestry Foundation Wharton Plantation and Bridge Street Woods and 12 acres belonging to Groton’s Conservation Commission Woodland Park Conservation Area, as well as the Trust’s Mason Back 100, 27-acre Cronin-Massapoag Land, and 20-acre Red Line Path. The Trust notes that these contiguous protected parcels complete two wildlife corridors, one running north-south along Cow Pond Brook, and one east-west from the Tyngsboro and Dunstable boundaries across much of northern Groton.


The property serves as a sanctuary for plants and animals and contains a variety of important habitats.  Maintenance of these habitats and refuges is a critical goal.

A full range of non-motorized activities are allowed including: Horse-back riding; Mountain biking; Hiking; Trail running; Snowshoeing; Nordic skiing; Nature study; and Photography.

Trail Maps

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