The Mariposa Museum and History Center is organizing a “Yosemite Climbing History” exhibition which will include artifacts, photographs, a time-line, and a series of speakers on various aspects of Yosemite’s climbing history. The opening of the exhibition will be on Friday, April 5^th with a “Ribbon-Cutting” at 6:00 p.m., followed by a slide show by Ken Boche of the first ascent of the Psychedelic Wall which he established in 1966.   The exhibition will continue at least through June, and pioneering climbers, Glen Denny, Ken Yager, Gary Colliver, and others will be making their own presentations over the course of the exhibition.