PETERSHAM -- This wall is a relic. Parts of it are tumbled, others bravely erect. The round stones are covered with lichen. Squirrels and chipmunks scamper across, starting as they disturb loose rock. The stone wall meanders into deep, damp woods through which Indians once passed and where, before the trees took over, early settlers grew corn.
This wall in the Harvard Forest is one of thousands crisscrossing New England's landscape. Walls like this are not just historical artifacts -- they reveal how New England came to be and how society evolved.
The Northeast has about 250,000 miles of stone walls -- enough to circle the equator 10 times -- and almost 99 percent of those are in New England. A good place to see some is throughout the North Quabbin region, about 70 miles west of Boston. The town of Petersham alone has at least 436 miles of walls and more remain hidden in woods.
"Stone walls represent our history and heritage," says Esther Shepardson, 89, of Athol. "The tradition to build them should be resurrected."
Stone walls were built by settlers engaged in clearing land. But they tell a deeper story. "North Quabbin's bedrock can be mapped using stones in walls because loose rocks occur close to the bedrock," says Michael Williams, professor of structural geology and tectonics at the University of Massachusetts at Amherst.
Wall stone, gray-tan Monson gneiss, finely layered black schist, and garnet muscovite biotite originated as volcanic rock from an arc of volcanoes off the coast of North America almost 500 million years ago. The arc was deformed and crushed against North America's coast 360 million to 420 million years ago. During this time of epic change, the North Quabbin region was created.
The bedrock has since changed again -- sheared, recrystallized, and broken down -- as Earth's land and oceans joined or drifted apart and North America moved from the Southern Hemisphere to its present position. In the last Ice Age, 18,000 years ago, south -moving glaciers eroded North Quabbin bedrock, chiseling huge , sharp rocks into smaller, rounder stones and spreading them in topsoil, where the settlers would uncover them .
The nine North Quabbin towns -- Athol, Orange, Erving, New Salem, Petersham, Phillipston, Royalston, Warwick, and Wendell -- were settled between 1730 and 1760. "Some towns were presented to families of soldiers who participated in the 1690 England-France war in Canada," says Allen Young, author of "North of Quabbin Revisited" (Haley's, 2003).
Settlers felled forests and cleared land of rocks and stone. The first walls were mere dumps along a field's periphery. Later people built more sophisticated walls. "You can look at a wall in the woods and imagine the early people who came and built it," says Robert Coyle, a geologist and Athol resident.
Harvard Forest was established in 1907 and has been an ecological research site operated by Harvard University since 1988. It is also the home of the Fisher Museum, dedicated to the study of the forest. Walking through the woods one recent afternoon, John O'Keefe, the museum coordinator, points to a wall 3 feet wide and 3 feet high. "This is a crop wall," he says. Walls of this kind, built with stone of all sizes, surrounded cropland where even small stones, an impediment to plowing, were removed. Every year the freezing and thawing of the soil brought more stone to the surface and the wall kept growing.
Farther along, O'Keefe points to a "pasture wall," which appears quite similar to a crop wall. But viewed close-up, it is not as wide and lacks small stones. Small stones, not a problem on pasture land, were not cleared.
Deeper into the forest there are numerous walls hidden partially in a dip of land . O'Keefe draws attention to a stone structure below ground level. This is a "cellar hole," the foundation of a house that probably burned down. The foundation's stones are arranged as if part of a stone wall, but below the ground, and in the center is a stone pile that supported the chimney.
Around the cellar hole are foundations of other buildings, barns, and various other stone walls. "From the stone work we can work out how the land was laid out," says O'Keefe. It is hard to imagine this land full of life . The house was apparently an inn, so people once stopped here for a drink or to stay the night . Today the muggy stillness of the afternoon is broken only by the gentle rustle of leaves.
The walls, of course, were not built in woods. Land was abandoned in the mid - 19th century as the Industrial Revolution drew people to cities. Natural forest grew back and small farms, rambling walls, and a way of life slowly disappeared.
As forest grew back, walls that were boundaries between different kinds of land became boundaries between different kinds of forests. "As you cross a wall it is common to see a different tree species on the other side," O'Keefe says. He points to a pasture wall separating forests of different ages. Because walls separated different land use s, soils on each side differ in nutrient richness and support different trees.
Almost 80 percent of the North Quabbin's 220,000 acres are forest -- perfect for stone wall exploring and other activities. The area has two big rivers, the Millers and the Swift, and nine large lakes, one of which is the 39-square-mile Quabbin Reservoir, which supplies water to Greater Boston.
Relatively undiscovered and largely devoid of tourists and gift shops, the North Quabbin, with 26,000 inhabitants, is a rural retreat. "This area is a hidden gem for recreation, scenic views, and quality artisan products few people know about," says Scott Maslansky, North Quabbin Woods project director for the New England Forestry Foundation.
A day trip from Boston is an easy drive, and bed -and -breakfasts offer accommodations for visitors. Area events such as the Thanksgiving Harvest Festival next weekend, the April River Rat Race and Parade , the Great Northern Tier Geocaching Tournament in August, or the Garlic & Arts Festival in September offer a glimpse of strong community life.
Each North Quabbin town is unique, but Petersham's town center with its magnificent common surrounded by mansions and old buildings is straight out of a picture book. Most towns sell wood products from lumber to fine furniture, and boast arts and crafts stores selling glasswork and ceramics.
For outdoors enthusiasts, there is hiking, fishing, boating, kayaking, cross -country skiing, and even sky diving near Orange. Tully Lake Campground in Royalston is popular with campers, and the gorgeous Doane's Falls is a short hike from the campground. Tully Lake is great for boating and has numerous islands to explore. A steel tower atop the 1,617-foot Mount Grace offers a stunning view in the fall and can be reached by hikers in under two hours.
While stone walls are ubiquitous, the Sunday Walls in Bearsden Forest in Athol are worth a visit. These walls, a total of 30 feet in length, located less than a mile from the parking lot off Route 2A, are interesting not for their size, but for their history. Lore has it that one Sunday in the mid-18th century, two farmers decided to compete in stone wall building. They picked a central point and built outward and the farmer who built the longer wall was declared the winner. His name is lost to history.
Their walls, however, still stand, testimony to life that was and witness to life that will be.
Contact Sena Desai Gopal, a science writer in Boston, at sena_desai@yahoo.com. 
