Hiking Backpacks / 3 Liter reservoir
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3L Hiking Backpacks

Catalog updated 2026-10-08

High-capacity bladders for all-day excursions in hot conditions 103 bags · 47 brands

For hiking For traveling For men Daypacks For camping For women Waterproof Ultralight Foldable & Packable For cycling Affordable Black Hydration bladders 20 Liter capacity Military & Tactical 40 Liter capacity Blue Sling bags Crossbody For climbing 30 Liter capacity 2 Liter reservoir For running 25 Liter capacity Green 10 Liter capacity 15 Liter capacity 35 Liter capacity 3 Liter reservoir Shoulder For hunting 50 Liter capacity Grey Reflective Gray Fanny packs Unisex 60 Liter capacity 1.5 Liter reservoir 70 Liter capacity Orange Insulated Purple Red Anti-theft Navy Army Green 2.5 Liter reservoir Nylon Canvas Khaki Brown Olive Tan

Best 3L Hiking Backpacks

# Brand Model Facts Tier See deal
1 CamelBak long neck hydration reservoir brown 9.4 CamelBak long neck hydration reservoir brown Hydration bladders · Military & Tactical $45.95
$45.95 See deal
2 Mardingtop Khaki 75L molle internal frame backpack Mardingtop Khaki 75L molle internal frame backpack Khaki · For hiking · For traveling $99.99
$99.99 See deal
3 Maelstrom hydration hiking backpack 20l Maelstrom hydration hiking backpack 20l For hiking · Ultralight · Hydration bladders $35.99
$35.99 See deal
4 Osprey Tempest 40L women hiking backpack black Osprey Tempest 40L women hiking backpack black Black · Women · For hiking $230
$230 See deal
5 HydraPak Contour ultralight hydration reservoir 3L clear 9.1 HydraPak Contour ultralight hydration reservoir 3L clear Ultralight · Hydration bladders $49
$49 See deal
6 CHERAINTI Army green 3L water reservoir pouch CHERAINTI Army green 3L water reservoir pouch Green · For hiking · For camping $16.95
$16.95 See deal
7 Platypus Big Zip EVO 3L Hydration Reservoir 9.4 Platypus Big Zip EVO 3L Hydration Reservoir For hiking · For traveling · Hydration bladders $59.95
$59.95 See deal
8 TAGVO Complete 6-in-1 Water Bladder Cleaner Set TAGVO Complete 6-in-1 Water Bladder Cleaner Set Affordable · Hydration bladders · 2 Liter reservoir $12.98
$12.98 See deal
9 Azarxis replacement water reservoir 1.5L capacity 7.3 Azarxis replacement water reservoir 1.5L capacity For hiking · For cycling · Affordable $12.99
$12.99 See deal
10 INOXTO Insulated hydration bladder with high flow valve INOXTO Insulated hydration bladder with high flow valve For hiking · For camping · For cycling $15.99
$15.99 See deal
Nearby sets
Hydration bladders For hiking For running For cycling 2 Liter reservoir For camping 1.5 Liter reservoir Military & Tactical

What a 3 liter reservoir is

A 3 liter reservoir is a water bladder that fits inside a hiking backpack. It holds enough water for a full day in hot conditions. The bladder connects to a drink tube so you can sip without stopping.

How it differs from smaller reservoirs

A 3 liter bladder carries more water than a 2 liter or 1.5 liter reservoir. The extra capacity matters on long exposed trails where refill points are far apart. It also adds weight, so you fill it based on the day.

Sizes and details

Reservoirs come in colors like black, gray, green, and blue. Some have a low-profile shape that sits flat against your back. Tube adaptors let you route the drink hose through either shoulder strap.

Packs that hold a 3 liter bladder

Backpacks in the 16L to 40L range often have a sleeve for a 3 liter reservoir. Women's-specific packs in 40L use a shorter torso that keeps the bladder high on the back. Daypacks at 20L can carry a 3 liter bladder for fast hikes.

Before you buy

3 liter reservoir questions

How long does 3 liters of water last on a hike?

In moderate conditions, 3 liters lasts most hikers about 4 to 6 hours. In heat or at high effort, you may drink it faster. Plan refills or carry a filter if the trail has water sources.

Will a 3 liter reservoir fit in any hiking backpack?

No. The pack needs a reservoir sleeve sized for a 3 liter bladder. Check the pack specs or measure the sleeve depth before buying. Many 16L to 40L packs have a compatible sleeve.

How do I keep the drink tube from freezing?

Blow water back into the bladder after each sip so the tube stays empty. Some tubes have insulated covers that slow freezing. In deep cold, carry the bladder close to your back for warmth.

Is a 3 liter reservoir better than bottles?

A reservoir lets you drink while moving without stopping to reach a bottle. Bottles are easier to refill and clean. Many hikers carry a reservoir plus one bottle as a backup.