Highest elevation 8268
YDS rating 5.4
Pitches 6

A glacier approach leads to a 50+ degree, 800-foot (240m) snow & ice gully, then to another 800 feet of rock climbing, ranging from class 3 to perhaps 5.4. Objective hazards include crevasses, a bergschrund, steep snow/ice, avalanches, and steep, loose rock. While a fast party can do it in a weekend, our threesome took until mid-afternoon Monday to get home. (SummitPost)

You also need a North Cascades Backcountry Use Permit

More info on SummitPost: https://www.summitpost.org/beckey-schmidtke/163780