Episode summary: In Mansfield, Connecticut, massive granite boulders aren't just lawn ornaments—they're community anchors, wedding venues, and the subject of a century-old mystery. This episode explores why this town has four times the glacial erratics of neighboring areas, from the unique pink-feldspar Mansfield Granite to the Willimantic River valley's glacial debris chute. We trace the science behind the "Wandering Stone" (which actually moves 3 inches per year), the 50-year tradition of the Mansfield Rock Fair, and the legal battle that saved Hannah's Rock from demolition. Discover how geology shapes identity—and why some things are too heavy to move, in every sense. Show Notes Mansfield, Connecticut has a boulder problem—or rather, a boulder abundance. With roughly 4.2 glacial erratics per square mile (more than double the state average), this town sits on an extraordinary concentration of massive granite rocks dropped by the Laurentide Ice Sheet 18,000 years ago. These aren't random rocks: they're Mansfield Granite, a medium-to-coarse-grained biotite granite distinguished by pink microcline feldspar crystals, making them instantly recognizable against the darker Bolton Schist of surrounding towns. The Willimantic River valley acted as a glacial debris chute during the ice sheet's retreat, funneling meltwater and concentrating the boulder deposit. The result: a landscape dotted with pink-hued monoliths, some weighing 180 tons, that have become central to Mansfield's identity. Residents named them—Pudding Rock, The Giant's Marbles, Whisper Rock—and built traditions around them. The Mansfield Rock Fair, running since 1972, draws thousands for boulder-balancing competitions and geology walks. The "Wandering Stone" has been measured moving 2.7-3 inches per year toward the Willimantic River for over a century, likely due to frost heave on a clay slope. In 1986, a legal battle under the Connecticut Environmental Protection Act saved Hannah's Rock from demolition, cementing these erratics as protected cultural landmarks. The takeaway: sometimes the most immovable objects become the foundation of community. Listen online: https://myweirdprompts.com/episode/mansfield-glacial-erratic-boulders