Best Trekking Backpacks (2026)

The Osprey Atmos AG 65L Small/Medium at $339.96 is the backpacking pack for torsos up to 20 inches (measured from C7 vertebra to iliac crest). The Anti-Gravity suspension is Osprey's engineering flagship: a tensioned mesh backpanel and hip belt that distributes pack weight across the back and hips with significant airspace between the pack and your back, reducing sweat and contact heat over long hiking days. Backpacking packs often define trip comfort more than any other gear choice for multi-day hikes — the Atmos AG's suspension is the reason it consistently appears at the top of serious backpacking gear recommendations. 65L volume handles a week's worth of gear for 3-season backpacking. Osprey's All Mighty Guarantee covers lifetime repair. The critical limitation is fit. The Small/Medium fits torsos up to approximately 20 inches. Buyers with longer torsos need the Large/XL at $339.99 — the same price. Fitting a backpacking pack to your torso length is not optional; an improperly fit pack transfers weight to the wrong body zones and causes fatigue and pain on day 2 of a trip. Measure before ordering. Best for: backpackers with short-to-medium torsos who want the best 3-season suspension system in a 65L volume at under $350.

The Osprey Atmos AG 65L Large/XL at $339.99 is the same pack as the Small/Medium with a suspension system sized for torsos above approximately 20 inches. The Anti-Gravity tensioned mesh suspension, 65L capacity, and All Mighty Guarantee are identical — the choice between Small/Medium and Large/XL is exclusively determined by torso measurement, not preference. For taller backpackers who are typically undersized in standard 'one size' packs — where the hip belt sits too high to transfer weight properly — the Large/XL suspension geometry positions the load transfer points at the correct anatomical locations for a comfortable multi-day carry. The practical note: at $339.99 versus $339.96 for the Small/Medium, the price is effectively identical. The only factor determining which to buy is your torso measurement. At outdoor gear retailers, you can be fitted in person to confirm the right size. For online ordering, Osprey's sizing guide with measurement instructions provides the determination. Best for: backpackers with longer torsos who need Large/XL fit for correct hip belt placement and weight transfer in a 65L suspension pack.

The Gregory Baltoro 65L at $369.95 is the alternative to the Osprey Atmos AG for long-distance backpackers who want a different suspension approach. The Baltoro uses Gregory's Response AFS (Auto Fit System) which automatically adjusts the hip belt and shoulder strap angle during movement to maintain contact as your hip position shifts while hiking. The result is a more dynamic fit that some backpackers prefer for demanding terrain where pack position shifts constantly versus the Osprey's static but well-tensioned suspension. 65L capacity and organizational depth matching the Osprey: front panel access, multiple hipbelt pockets, and Osprey-comparable organizational features. Gregory's warranty covers materials and workmanship. At $369.95, the Baltoro costs $30 more than the Atmos AG. The comparison is close enough that the decision comes down to personal fit preference — the Osprey is the category incumbent with broader familiarity, and the Gregory is the alternative for buyers who've tried the Osprey and prefer the Gregory's dynamic hip adjustment. Both are correct purchases for serious backpackers. Best for: long-distance backpackers who prefer dynamic auto-adjusting hip belt suspension over static tensioned mesh designs.