But height alone isn't the key factor in pack fit—it's torso length, or the distance from the point on your lower back that's level with your hip bones, up to the base of your neck (technically, the seventh cervical vertebra). The majority of packs are sized to fit torsos of up to 18 to 19 inches, which probably isn't enough for you. So you need to look for a pack that goes to 21 inches of torso length or more.
In off-the-shelf packs, that means a pack that comes in as many sizes as possible. One example would be the Gregory Whitney ($329 U.S., www.gregorypacks.com). The pack in its large size can accommodate a torso length of 21.5 inches, which should be just about right for you. It's also an excellent pack, with lots of capacity for long trips (nearly 6,000 cubic inches, or 97 liters), top- or front-loading design, lots of organizational pockets, and an excellent suspension.
Arc'Teryx's Bora 80 ($369, www.arcteryx.com) handles even longer torsos—up to 23 inches. It has a slightly smaller pack bag than the Whitney, but at 5,500 cubic inches (90 liters) it's still plenty large for long trips. It too has a superb suspension for big loads, plus a high level of water-resistance and good organizational features, such as sleeping-bag compartment and lots of access zippers.
The pack with the most torso length, though, is Osprey Packs' Crescent 90 ($379, www.ospreypacks.com), which fits up to 24.5 inches. Fortunately, it too is an excellent, high-end pack. Big capacity, great suspension, rugged construction.
Have a friend help you measure your torso, then start shopping. All of these packs will work well if they fit. They're made for big loads, and handle them with aplomb.
More of the best backpacks reviewed in Outside's 2004 Buyer's Guide .