It looks like the most difficult part of Cody Townsend’s project to bag the 50 Classic Ski Descents of North America over the next three years won’t necessarily be the ski descents, but the climbs to access them.

The Fifty Episode 8, The Sphinx, Alaska

Townsend navigates the knife-edge ridge of the Sphinx. 

To make an already intimidating project even more intimidating, Townsend decided at the outset of his three-year-long quest that he wouldn’t take the easy out—that instead of getting heli assists to the top of each line, he’d climb up to them. So in Episode 4, the pro skier puts in a six hour ascent to ski the Hypodermic Needle; in Episode 6, he climbs 8,000 feet to the top of Mt. Currie; in Episode 7, he and his crew muscle their way up to the top of Joffre Peak—twice—via a sketchy, exposed couloir.

Catch up: The Fifty Episode 7, Joffre Peak

The Fifty Episode 8, The Sphinx, Alaska

How steep is a 50-degree slope? This steep. 

While those climbs were spicy, they didn’t put Townsend on edge as much as bootpacking up the sustained 50-degree slope and the knife-edge ridge of the Sphinx in Episode 8.

To ski the Sphinx, one of the most iconic big-mountain lines of the Chugach Range in Alaska, is no joke. But as Townsend discovers in this episode, to climb up the top of the steep, exposed line requires even more mettle. 

“For climbing you have to have a lot more special conditions, meaning stability and [the snow] is not too deep," says Townsend. "It’s kind of a hard opportunity to pass up because these lines are no gimmes, and they’re lines that have been on my mind as being one of the most difficult points of this entire project.” 

Watch "The Fifty" Episode 8, The Sphinx

Tune in every two weeks to catch a new episode of Townsend’s big adventure of skiing the 50 Classic Ski Descents of North America. You can also follow along with Townsend's project via Instagram