Your backpack is the single most important piece of gear you’ll carry on the Appalachian Trail. Get it wrong, and every mile will be miserable. Get it right, and you’ll barely notice it’s there. Here’s how to choose a pack that actually works for your body and your hiking style.

Picking the Right Capacity
Most thru-hikers need a pack in the 50-65 liter range. Bigger packs just tempt you to fill them with stuff you don’t need, adding unnecessary weight. If you’re finding that a 50-liter pack feels too small, the problem isn’t the pack. It’s that you’re bringing too much gear.

The exception is if you’re hiking in winter or carrying specialized gear like photography equipment. In those cases, a 65-70 liter pack makes sense. But for a standard spring-through-fall thru-hike, stick with the 50-65 range.

Fit Is Everything
A pack can have every feature in the world, but if it doesn’t fit your torso length and hip structure, it’s useless. Most outdoor stores offer free pack fittings where they measure your torso and help you adjust the pack properly. Take advantage of this service.
The hip belt should sit on your hip bones, not your waist. This is where most of the weight should rest. The shoulder straps should wrap comfortably around your shoulders without gaps or digging in. Load lifters at the top of the shoulder straps should angle back at about 45 degrees when properly adjusted.

Test the pack with weight in it. Load it up with 25-30 pounds and walk around the store for at least 15 minutes. A pack that feels great empty might be torture once it’s loaded. Pay attention to any pressure points or rubbing.

Features Worth Having
You don’t need a pack with a million pockets and compartments, but certain features make trail life easier. Hip belt pockets are essential for keeping snacks, your phone, and small items easily accessible. A brain (top lid) with pockets gives you quick access to frequently used items. Side water bottle pockets that you can actually reach while wearing the pack save you from stopping constantly.

Some packs come with a built-in rain cover. Others require you to buy one separately. Either way, you need rain protection for your pack. Sleeping bag compartments with separate access are nice but not essential. Same with trekking pole attachments and ice axe loops.

Break It In
Just like boots, your pack needs breaking in. Wear it on training hikes with increasing weight. Adjust the straps until you find the perfect configuration, then take notes or photos so you can replicate it. Your body will adapt to carrying weight, but give it time to do so gradually.