When Sam Boyce and I did the first ascent of the south buttress of Whatcom Peak (7,574’, 48.85032, -121.38347) in 2022, via Castle in the Sky (2,000’, IV 5.10b; see AAJ 2023), we vowed to come back for the southwest ridge. The south buttress had quite good rock for the Northern Pickets, and the southwest ridge looked like an easier version. We even hoped it might be a fun alternative to the notorious chasm of Imperfect Impasse for those doing the Northern Pickets traverse.

In summer 2025, I found myself dreaming of climbing in the alpine in a way I hadn’t in a few years, and we headed for Whatcom’s southwest ridge in late July. We did the approach from Hannegan Pass in six hours and made camp on the summit of Easy Peak. Remembering that the south ridge had only taken us six or seven hours to climb, and theorizing this route would be easier, we figured there was no need for an alpine start.

After doing the final drop from Easy Ridge to the toe of Whatcom’s southwest ridge, we started up around 9:30 a.m. From the get-go, the climbing was chossier and harder than it looked—and it only got worse. After nine slow, loose pitches—with several up to 5.9 and 5.10—we finally arrived at the massive saddle that separates the lower and upper halves of the ridge, reaching this point much later than hoped, around 3 p.m.

Up close, the upper ridge looked steeper, longer, and more complex than we’d expected. Why hadn’t we carried one sleeping bag, just in case? I was all for bailing at this point, but Sam convinced me we should give it a proper look.

Luckily, the terrain was again different than it appeared—this time in our favor. We found a weakness that allowed us to mostly simul or solo mellow terrain. The rock remained quite broken, with few options for anchors or protection, but it mattered far less when the difficulty was only 5.5. There was even an enjoyable knife-edge.

We summited the 2,400-foot-long ridge at 6 p.m. and tagged the south summit, then started the circuitous descent that took us through the Imperfect Impasse. We were disappointed that we had not found a reasonable alternative to the Impasse, but happy to have spent a safe, albeit slightly stressful, day in the mountains on The Imperfect Bypass (IV 5.10+ R).

—Lani Chapko