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Photo: Marcbela (Marc N. Belanger), Public domain via Wikimedia Commons
The Knowlton Hat Factory is a historic factory building in Upton, Massachusetts.
© OpenStreetMap contributors
The 2,660 acre forest offers hiking, biking, horseback riding, cross country skiing, and snowmobiling. Dotted with ruins of old structures. Trails are fairly developed so it's an easy hike.