From the south end of Washington Lake you’ll find the widest gully in the ridge above, and boot up it. This will be the first major gauge of snow conditions, as this gully itself can present hazards. Once on top, you’ll enjoy your first view of Castle Peak––and it’s quite the view. Dead ahead are the striking couloirs of Castle’s ragged SW face, though the S-face line remains out of sight. From there you’ll get a few hundred feet of descent into Chamberlain Basin. Continue across a lake and go over a forested knoll, then you can begin to traverse the south slope of Castle. You may choose to go lower and give wider berth, depending on the look of the chutes above.

The final test for conditions comes at the base of the south face, where you’ll stare straight up a massive, yawning gully. It forks into other couloirs and feeder chutes that could be explored, but the route mapped here goes straight up the gut of it. There is one notable couloir about ⅔ of the way to the top that is often skied instead of the main gully, however, so take your pick. Top out on the ridge, if not the actual summit, and find stupefying views down the precipitous north face. Then turn and enjoy your hard-earned Fifty Classic descent!

Sources: https://noahhowell.com/2019/10/30/castle-peak-id/ http://idahoalpinezone.com/index.php?p=292 http://mt-adventures.blogspot.com/2015/02/white-cloud-mountains-castle-peak.html