Planning for an AT attempt. What size backpack do most folks use?

[Seesfar]

Thanks! I would appreciate your input.

[Fallesafe]

I did it with a 55L backpack (the Hyperlite Windrider 3400). I loved the bag. It was absolutely awesome. And it was exactly big enough. Any less and I would have been running into space limitations all the time.

[Slo-go'en]

Kind of depends on when you start and what you have for gear. 65L is pretty common for a March start due to needing a fairly bulky sleeping bag and warm and extra clothes. If you start in mid-April with milder temps and weather, a 55L should be sufficient. Basically, there are two approaches. 1) pick the gear to fit the pack, or 2) pick the pack to fit the gear.

[Miner]

Size your backpack to fit your gear. Get all your other gear figured out and then find a pack that will fit and carry it all comfortably.

[HankIV]

Size your backpack to fit your gear. Get all your other gear figured out and then find a pack that will fit and carry it all comfortably.

This, and remember you can buy gear that is light, cheap and high quality…pick two.

[peakbagger]

Its highly likely that whatever pack you start with is going to be way too big somewhere in northern Virginia. Eventually the smaller pack you replace it with will be too small once you hit NH if you are running late.

[Kittyslayer]

In my training hikes of 5-6 days I have been using a 60L pack. I hate a bunch of crap hanging outside my bag. The 60L lets me put nearly everything inside unless I have a big food haul. I don't always pack it full as I try to only carry what I need and it compresses down well.

[scope]

I would absolutely take my Catalyst, which is listed as 75L, but that includes the side, back and hip pockets. The main body is about 50L which is plenty large, but what I like is that it cinches down to carry a small load very well. Its reasonably light and I never have to worry about packing it as it will swallow more than I should carry. The other pockets as mentioned are larger than other packs which means you have a little more flexibility for how you utilize them - like carrying a plus sized iPhone in the hip.

[Seesfar]

I would absolutely take my Catalyst, which is listed as 75L, but that includes the side, back and hip pockets. The main body is about 50L which is plenty large, but what I like is that it cinches down to carry a small load very well. Its reasonably light and I never have to worry about packing it as it will swallow more than I should carry. The other pockets as mentioned are larger than other packs which means you have a little more flexibility for how you utilize them - like carrying a plus sized iPhone in the hip.

I’m late replying but thank you so much

[OhioHiker]

Thanks! I would appreciate your input.

Whats your loadout look like?

[MtDoraDave]

The original post leads me to believe the OP doesn't have all of his or her gear yet.

One of the biggest space savers or volume consumers is or will be your sleeping bag/ quilt. An inexpensive one will usually be bulky (and heavy), taking up lots of space in your pack which would make you carry a larger pack.
Often times when we carry a larger pack - say a 75 liter - we will fill it up. When we do that, they get heavy.

One of the places that I recommend spending the extra money is on a good quality, lightweight, quilt or sleeping bag. After years of carrying a less expensive bulky bag, I finally spent the money on an 850 fill Enlightened Equipment 10-degree quilt. Very light and compressible compared to my old sleeping bag(s).

Getting "lightweight" is a little expensive, getting "ultra-light" is quite a bit more expensive. The cheapest way to be "lightweight" is to leave the "maybe I'll need this" items at home.

Plenty of people have carried heavy bulky backpacks all the way to Katahdin, but the lighter you can get your backpack, the better your odds are of making it. Also, the lighter the pack, the less likely you are to get injured, the more mileage you can do per day or the less fatigue you will have at the end of each day of hiking.

After saying all that, as a one-week at a time section hiker, I have a 75 liter Osprey for cold weather (below freezing) trips and a 65 liter ULA Ohm for warmer weather trips. Sometimes, as a section hiker, I carry the whole week (8 days) of food - which takes up a lot of space.

[Starchild]

Often times when we carry a larger pack - say a 75 liter - we will fill it up. When we do that, they get heavy.

Do we? I've heard this many times but I certainly don't, and while I'm sure there are some who do, I don't buy that's the majority of experienced LD hikers.

On my thru I typically had my summer weight down that all the cinch straps were at their max compactness. What a larger pack does is give you more options on how to pack and easier to pack and also to get the stuff one needs. This tends to allows an overall more comfortable pack as well. While the smaller pack folks were playing tetris most every time, especially leaving town resupply and getting ready for a longer stretch till next one, Sometimes even carrying a meal in hand. I could easily pack up and get on trail putting things were I wanted in the shape I wanted instead of where and how they needed to be.

In that I do like some extra room, but not so much as I feel it is unnecessarily large, with the primary factor of comfort under a load.

[QiWiz]

Would go with 60L if you want one pack for the whole shebang. Bigger than you need for some of the trek, but large enough for more insulation or food when you want those things. I’m assuming you will select only the necessary stuff. If not, maybe go bigger, but you may regret it.

[MtDoraDave]

Do we? I've heard this many times but I certainly don't, and while I'm sure there are some who do, I don't buy that's the majority of experienced LD hikers.

On my thru I typically had my summer weight down that all the cinch straps were at their max compactness. What a larger pack does is give you more options on how to pack and easier to pack and also to get the stuff one needs. This tends to allows an overall more comfortable pack as well. While the smaller pack folks were playing tetris most every time, especially leaving town resupply and getting ready for a longer stretch till next one, Sometimes even carrying a meal in hand. I could easily pack up and get on trail putting things were I wanted in the shape I wanted instead of where and how they needed to be.

In that I do like some extra room, but not so much as I feel it is unnecessarily large, with the primary factor of comfort under a load.

I didn't specify, but I was referring to newbies, not experienced ld or thru hikers. There is definitely something to having a larger pack to be able to carry larger food loads when necessary.
If I were to do a thru, and didn't have the ability to swap out packs when the weather warmed up, I'd probably use my Osprey 75 liter rather than my smaller and lighter ULA pack...but since I have both, I'd swap out packs when I swapped out my 0 degree bag and extra layers.

[HankIV]

What MtDoraDave said, and even more so at 67.

[peakbagger]

Remember to factor in a bear can, per the ATC they are now strongly recommended. My suspicion is the vast majority of those responding did not carry a bear can. Its a whole new ball game for AT hikers, less of issue for PCT folks who are required to carry them on at least one section the PTC.

[wyclif]

You won't need a bear can. There's only one short section of the trail that requires a bear can, and you can easily hike through it in less than a day if you plan accordingly.

[annoydbear]

I agree with Peakbagger. The ATC is recommending bear canisters for 2023.

I’m planning a 2024 thru hike and have pivoted to a larger pack to allow me to carry the canister. I don’t want to contribute to bears being euthanized because of careless food handling. I hope others are moving in this direction too. Bear canisters help protect the bears.

I’ve got an Osprey Exos 58 and just bought an Osprey Aether 65 that should better accommodate the bear canister I bought. If not I will go bigger. I won’t carry any extra gear than what i was already planning to carry - just want to be comfortable with the canister in my pack.

[scope]

You won't need a bear can. There's only one short section of the trail that requires a bear can, and you can easily hike through it in less than a day if you plan accordingly.

This is true, but not exactly truth. I'm not quite sure why there haven't been bear can recommendations in other sections - for example, the section on the other side of Neel Gap, or between Muskat shelter and Betty Gap - where there have been issues with bears raiding areas where there is consistently hung food to go after, which they happen to be quite adept at. So, I can't say I believe its true that you won't need one just because the formal restricted area is only 5m. I think what might be true is that you could end up wanting one, and it would seem to be an increasing probability.

And then regarding pack size, sometimes you have to ensure the opening of the pack can accommodate the bear can. Most 50L+ packs can with no issue, but a lot of 35L packs can't, and its dicey with some 40-50L packs. My other pack is a CDT and it accommodates my BV450 rather easily. That said, it was recommended earlier in this thread as a main pack which I vehemently disagree with. Its frameless and has no load lifters. Its volume is larger than other small frameless packs which is great for putting my insulation in and letting other small summer gear pack into that to form a consistent feel on my back. I think it could be a great AT pack for a more experienced hiker, but I'd never recommend it here to a general inquiry on packs.

[wornoutboots]

I agree with Peakbagger. The ATC is recommending bear canisters for 2023.

I don’t want to contribute to bears being euthanized because of careless food handling. Bear canisters help protect the bears.

With this logic by the ATC, please let us know how many bears have been euthanized due to AT Thru-hikers