A long-overlooked sheer wall looms in the Washington Pass area, northeast of Wallaby Peak in the Cedar Creek basin. The tower-like feature, known by locals as the Mushroom, is a subpeak of Half Moon, with an overhanging wall on its southeast face, composed of beautiful Golden Horn granodiorite. In his Cascade Alpine Guide, Fred Beckey simply labeled it “dome.” The summit can be reached by a scramble, but even though many climbers have sought a way up the Mushroom’s southeast face, it was still unclimbed when I first sat at its base in the fall of 2024.

Armed with binoculars, I spent two days meditating, embracing the pristine basin, and studying the wall in various lighting. There were cracks, but they all trended the wrong way, toward less aesthetic portions of the wall. Midday on my second day of scouting, the serpentine shadows of a long crack system popped into view. It seemed to run up most of the wall—it would just be a matter of navigating blank sections at the start and finish.

Nearly a year later, on October 3, 2025, Mark Allen and I started up the route, aiding toward the crack system on hooks, clean gear, and the occasional bolt or rivet. Much to our surprise, we found abundant, weathered-out crystal pockets, which made for excellent natural hook placements in addition to bat-hooks. When we entered the crack system, it graciously accepted beaks and small cams. We ran out of time after a few days and fixed ropes from our high point on pitch six, rappelling under a full moon.

Mark and I returned on October 17, after the first fall storm. To our surprise, wind had blown part of our line around a dead tree 70 feet up the first pitch. I drew the short straw and began gingerly jugging up the rope. After about 30 feet, I heard a crrrackkkk and went flying. Thankfully, the wall was so steep I just swung into space.

The rest of the climb went smoothly, save for a short fall when I blew a hook and fell onto another hook halfway up pitch seven. We finished Mother of Exiles (660’, 7 pitches, IV 5.8 A3+) in a 24-hour push. As we topped out in the darkness of early morning on the ice-capped dome, we were dazzled by the light of the aurora.

—Marshall Trautman