Twin Sister High Route. An easily accessible alpine training ground during the 1980s, the Twin Sister Range on the western edge of the Mt. Baker Wilderness is now isolated behind miles of private and gated logging lands. From May 12-14 Mark Allen, Dr. Greg Balco, Paul Kimbrough, and I made the first known ski traverse (V class 4 AI1 50°) of the entire range, going from south to north: Step Sister Peak to North Twin Sister Peak. The first day involved whiteout navigation in the morning and ski descents of the north faces of Last Sister Peak (5,562') and Saddle Slab Peak (5,802'), as well as a traverse along the east side of the range beneath Nancy, Barbara, and Trisolace peaks, and across the third largest glacier/ice field in the range, which we christened the Ripple Glacier.
On day two we crossed to the west side of the range at Saddle Slabs, skied the North Face of Cinderella (6,480'), and watched Mark ski the proudest line of the trip—the South Couloir of Little Sister Peak (6,600'). Crossing a series of cols past Hayden and Skookum peaks led to the technical crux: crossing the range for the third time to gain the Sisters Glacier just south of South Twin Sister Peak. What we expected to be a simple mixed and steep snow climb proved to be 40m of 4th-class rock followed by 100+m of 50° ice and mixed rock. Our thin rack (one hex, two cams, four stoppers) and short 8mm ropes (one 20m, one 30m) meant that we had to pitch it out on the rock and haul packs and skis, then Mark and Paul simul-climbed on one rope while Greg and I simul-climbed on the other. When we reached the ridge at sunset, we were surprised to find not a simple ski descent, but 100+m of rappelling. Double-rope rappels and down-climbing shenanigans led to a final fixed 40m single-strand rappel with a knot pass. We started setting up camp at 2:00 a.m.
Day three was incredibly hot, and we were incredibly tired. Looking up, we realized we had crossed the ridge several hundred meters farther south than we intended and had rappelled down the tallest aspect of a buttress we tagged Mirage Peak. Reconnaissance proved that our intended ascent would have required a 5th class pitch; our actual line was the best possible. The loss of our ropes and two cams in the rappels meant that our intended climbs and descents of South and North Twin Sister Peaks had to be scrubbed, so we spent the day skiing the Sisters Glacier, crossing back to the west and hiking out the last five miles to the car.
We actually traveled for 30 hours over three days, covered 26 miles, gained 12,000', descended 14,000', skied every single permanent snowfield/ice field/glacier (except for the Twin Glacier) according to the USGS map, and made significant descents across the range.
Special thanks to John Scurlock for his aerial photography.
Chris Simmons, AAC