On June 13, Len Vanderstar and I set out on an expedition to make the first ascent of Thunder Mountain (9,097’, a.k.a. Mt. Nirvana) without air support. Before 2016, this peak—the highest mountain in the Northwest Territories—had seen five documented ascents, all relying on support from helicopters or floatplanes. I had also made an unsuccessful attempt on the summit in 2015, helicoptering in from Watson Lake to try a new route on the southwest face with Dave Custer and Susan Ruff. On that trip we climbed to within a few rope lengths of the summit ridge, but retreated after encountering unprotectable rock.

From the mining town of Tungsten, Len and I put in our boats and paddled down the Flat River with Ron Vanderstar and Luke Weyman. After two days of difficult whitewater, involving many portages, we took out at an unnamed stream, stashed our boats in the trees, and headed into the Ragged Range. Three more days of tough bushwhacking, a glacier crossing, and alpine meadows brought us to the base of the east face of Thunder Mountain.

We had happened upon a rare sunny and warm weather window, and so we approached the face early the next morning. Ron and Luke helped Len and me haul gear to the top of the glacier at the base of the climb. Then Len and I continued the ascent while Ron and Luke returned to camp. I led three moderate pitches up the lower rock band, then built a solid anchor on a well-protected ledge just below the upper snowfield. The sunny, warm weather was not actually the godsend we had expected, because by this time the upper snowfield had warmed enough that multiple avalanches were releasing.

Len and I decided to wait until the snowfield went into the shade, hoping the snow might stabilize. After four hours, though, a small avalanche released directly above us. Our ledge was protected so the snow passed over us, just spraying us lightly, but we were rattled enough to descend for the day.

Back at camp we slept for a few hours, then started another attempt at midnight. This time we reached the upper snowfield at 3 a.m., when it was still firm, and easily made it to the base of the upper face. I led nine pitches of moderate but wet rock, up to 5.7, until we reached the left side of a long, horizontal ledge. I believe our line roughly followed the route of the 1996 expedition led by Jack Bennett, which made the first ascent of the east face. (This is the only known route on the face.) We donned crampons and traversed several pitches to the right on snow, then climbed three moderate rock pitches to the summit ridge. Here we took a nap and then continued up easy snow and fourth-class rock to the summit, where I lay on my stomach to reach up and tap the highest point, the top of a cornice overhanging the north face. It was the morning of June 21, the first day of summer.

We took another long nap on the summit ridge to wait for the evening chill to firm up the upper snowfield again, then rappelled the route through the night, returning to camp 51 hours after leaving. Ron and Luke headed back to the boats that day to paddle out, and Len and I rested a few days while the usual rainy weather of the area returned.

On June 25 we started our journey back to the truck at Tungsten. We scrambled partway up a gully just east of the Minotaur, then climbed four pitches of moderate snow and rock to a high col, and then rappelled into the north cirque. Three days of hiking brought us to the west edge of the Ragged Range, and we had enough extra time for a brief side trip to unclimbed Peak 46. We crossed the northern glacier, Len led a few steep snow pitches, and then I led a moderate rock pitch across a knife-edge ridge to the crumbling summit.

The next day we dropped into the Flat River Valley, and three more days of difficult bushwhacking brought us back to the truck at Tungsten. To finish the trip, we drove down to Blackstone Landing to pick up Ron and Luke at the end of their paddle.

– Eric Gilbertson, USA