Starting from the Emerald Lake Campground, proceed directly up the Northwest side of the West Rosebud Valley. Staying on the right side of Chicken Creek.
The idea is to get to punch through the thick timber and obtain the ridge on the Fishtail Plateau that is above and to the right of Chicken Creek. Once above the timberline, follow the ridge and you will be able to see Pyramid mountain come into view. Continue to follow the ridge until you are directly across a large bowl from the summit. Next, circle around the end of the bowl and head up the West Ridge of the mountain.
Bring a raincoat( in anticipation of the afternoon thunderstorms), plenty of water (there isn't a lot up there), trekking poles are nice to have, and good boots for touring around off trail. In the winter you might want crampons, an ice axe, and snowshoes; I haven't yet climbed it in the winter, so I don't have any good recommendations yet.
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