Southwest Twin is a 4,357-foot trailless peak in the Twin Range of the White Mountains, extending southwest along a wooded ridge from South Twin Mountain deep into the Pemigewasset Wilderness. Reaching the summit requires off-trail navigation; there is no maintained trail. The peak appears on the Trailwrights 72 and is widely regarded as the most demanding bushwhack on that list.
The standard approach totals roughly 14 miles and 3,700 feet of elevation gain. Most parties follow the Gale River Trail, Garfield Ridge Trail, and Twinway to the open summit of South Twin Mountain, then depart the trail to follow the ridge southwest. The off-trail section covers about a mile, skirting an unnamed 4,723-foot peaklet before descending to a col and climbing to the true summit. The terrain alternates between open boreal forest with moss-covered ground and patches of dense spruce-fir scrub and blowdowns; staying on the high ground and tracking the tallest trees helps avoid the worst tangles. Splitting the long approach with a night at Galehead Hut is a popular option.
The summit sits entirely below treeline in dense forest, so there are no views. Carry a map and compass; the thick canopy makes navigation by landmarks unreliable. Snow and ice can linger on the ridge and in the col well into spring.
