From the 2WD trailhead, drive up FR 102 where you'll find marked camping spots along the first 1.25 miles. Near 10,200' and 1.3 miles up the road, reach a creek crossing which has a footbridge -
1. If the road is open/clear beyond this point and you have a 4WD vehicle, you can drive higher. Low-clearance vehicles should NOT attempt this crossing, especially in early summer when the water is high. If you plan on driving across, it's best to walk over the footbridge first to see what you're up against. Cross Castle Creek and continue nearly 2 miles to the Pearl Pass road junction, at 11,150'. Turn right at the junction and follow the road up into Montezuma Basin -
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5. Pass the Montezuma Mine and continue another 0.5 mile to the end of the road, at 12,800' -
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From here, you are looking southwest at a steep slope/headwall that has snow through much of the year -
7. Climb 500' up the headwall to reach the upper basin (13,400') between Castle Peak and Conundrum Peak. Castle's north face is straight ahead and the north face couloir is on the left side of the face -
8. Continue south across the basin toward the base of the couloir -
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10. It may be easiest to hike toward the left side of the basin before angling into the bottom of the couloir.
Below 13,600', reach the base of the couloir and start climbing it south toward the northeast ridge -
11. The couloir is not that steep but should only be climbed with continuous, stable snow. Continue climbing (
12) to 14,000' where the couloir becomes slightly steeper (40 degrees max) -
13. Behind you there are great views of Conundrum Peak -
14. Continue to the top of the couloir to reach a saddle on the northeast ridge. From the 14,100-foot saddle, turn right and climb southwest up the final 150' of the northeast ridge - (
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16) to reach the summit -
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