This route requires careful route finding, but if done correctly can be a 4-7 hour (car to car) scramble vs the Stephens Lake Approach (the only other non technical way) which takes at least 8 hours of mostly off trail difficult travel.
From the Redfish Lake backpacker parking lot take the Fishhook Creek Trail all the way until the end and continue cross country for 1/4 mile. At this point cross the valley (go south) through possible swamp thickets and look for the prominent steep valley running perpendicular to the Fishook Creek Valley and East of the Horstmann Peak Summit ridge. Rise out of the swamps and into this gulley staying on the right side of the steep creek (west side). Soon you emerge into a hidden alpine bowl on the south side of Horstmann with views of Heyburn and the Fishook Spire.
From the major alpine bowl on the south side of Hosrtmann, there are 3 major gullies up the south face of Horstmann. The gulley to the leftmost (west) is the least technical (Class 3). The other two gulley offer hard Class 4 or Easy Class 5 scrambling to the summit. Mountain Goats are common in this vicinity and I saw 4 when I was there. The summit register is stamped "Mt. Hancher" - the original name left by the Iowa Mountaineers in 1954. Dave and Mariam Williams were some of the original scramblers and climbers in the area (Williams Peak is named after them). Luis Stur's signature is in the original summit log (Mt. Heyburn's Stur Chimney is named after him). The log has dates all the way back to 1954 and averages no more than 1 per year with some years in the 1980's seeing no one!
An axe could be handy early season, but just some route finding skills, a map, and maybe desert gaiters to keep the scree, sand, and snow out of your shoes.
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