You need a pack with a really good suspension, as my guess is the load will be in the 60- to 70-pound range. Ill recommend three:
Arcteryx Bora 80 ($375; www.arcteryx.com): Its not a huge pack, but its big enough for your trip (just shy of 5,000 cubic inches in the medium size). The Bora 80s first-rate suspension wont sag under a big load, and it has plenty of adjustments for good comfort. Its complete with a lower sleeping bag compartment, hydration-bladder pocket, and plenty of exterior tie-on points, so youll have lots of places to lash ropes and other climbing gear.
Gregory Whitney ($339; www.gregorypacks.com): The Whitney is a little larger than the Bora 80 at 5,400 cubic inches. It has more organizing options, with two large side pockets and a large back pocket, compared with the Bora 80s single, large back pocket. But the design is also a bit more complicated, leaving some people to prefer the Boras cleaner approach. That said, the Whitneys highly adjustable suspension, organizing options, and ample external lash points make it an excellent backpacking/mountaineering pack.
Lowe Alpine Contour 80+15 ($239; www.lowealpine.com): This is about the most pack for the money on the market. Its sturdy and roomy (4,900 cubic inches, plus an extendable lid for overflow), with a comfortable harness system that can handle big loads. Plus the Contour boasts lots of packing-friendly features such as plenty of pockets and lash points. If youre on a budget, this is the pack for you.
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