To get to the access road for these two mountains from Hailey, Idaho, drive north on Highway 75 through the town of Ketchum, then over Galena Summit at 8,701' and down into the Sawtooth Valley.
Shortly before reaching the small hamlet of Sawtooth City, or Smiley Creek as some call it, near the headwaters of the Salmon River, look for a sign indicating Pole Valley Road leading northeast from the main highway. Turn here.
Drive 2.4 miles east across the Sawtooth Valley until reaching a junction with Pole Creek Summit Road. Follow this fork and drive on this somewhat gentle dirt road until reaching the signed turn off for the Grand Prize Gulch Road.
From here, drive approximately .9 miles until reaching a point where two small streams flow in from the west. Park here on the side of the road.
The Yin and Yang route is named for the extremes of two different mountains that can be found right next to each other and the peace that can be found in between.
In this case, the gentle slopes of Peak 10,041 clash with the gnarliness of Peak 10,166 less than one mile away and the peace that is found in the unknown and picturesque basin below the two.
It is important to this route counterclockwise.
From Pole Creek Road, take the northernmost stream leading from the slopes above and bushwhack to the west until breaking into the basin below the two peaks. Continue to follow the stream as it curves northward.
Follow it until the terrain looks appealing to the west. Turn northwest and gain the faint east ridge of Peak 10,041. Scramble the ever steepening talus slopes to the summit.
Turn south and follow the connecting ridgeline to the summit of 10,166. The terrain becomes steep and slightly exposed at the near the top but remains class II.
Descend by returning to the saddle between the two peaks and descending the scree slope to the boulder field below the northeast face of Peak 10,166. Return to the small stream leaving the basin and back the to parking area.
No essential gear required. Those with climbing abilities may enjoy scrambling around on the rougher terrain of Peak 10,166 but be aware, the rock is rotten in the area.
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