MISQUAH — The Peterson barn, a great gambrel-roofed landmark that has stood on the rise east of town since 1901, is getting a new roof this summer — a development that has drawn quiet, genuine satisfaction from a community that has watched too many such barns sag, lean, and finally fold into their own foundations across the surrounding countryside.

The barn, built by the current owner’s great-grandfather and raised, by family tradition, in a single long day with the help of every neighbor who could swing a hammer, is among the oldest structures on the Chain still in daily use. At 125 years it has outlived the draft horses it was built for, the dairy herd that followed them, and most of the barns its builder would have known, which have come down one by one as their roofs failed and their families aged out of the labor of keeping them up.

It was the roof, as it always is, that forced the question. A barn roof is the whole difference between a barn and a slow ruin, and the Peterson roof had reached the point at which doing nothing meant losing the building outright. The family — declining, in the local manner, to discuss the cost beyond confirming it was “a number that made us think hard, and then think about Great-Grandpa, and then write the check” — opted to save it, hiring a crew that specializes in the old structures and their old, steep proportions.

The area historical society, which has documented the barn and would dearly love to document fewer demolitions, hailed the decision. “Every one of these we lose, we lose for good,” said a society member. “You cannot rebuild a hundred-and-twenty-five-year-old barn. You can only keep the ones still standing standing. The Petersons just bought theirs another fifty years, and the rest of us get to keep looking at it, which is no small thing on a county road.”

Work is expected to continue through the summer. The barn, newly roofed, will remain what it has been for a century and a quarter: too big for its present use, too dear to take down, and visible from the county road, where it has marked the eastern edge of the known world for longer than anyone now driving past has been alive.