Matthew Putney / For The Times
BRAINCHILD: Don Briggs, a physical education instructor at the University of Northern Iowa, got the idea to turn silos into climbing walls a few years ago. He hoses down a quartet of the storage facilities after harvest Iowas frigid winter temperatures do the rest. Briggs students help him maintain hoses and water pumps, and all climbers must sign a liability release form. Anyone is welcome to climb at no charge.
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