The Hydro Flask Sling Bag Is Perfect for Travel

From the trails of Maine’s Acadia National Park to sightseeing in Thailand, this mighty sling backpack carries all of my essentials and keeps me hydrated.

Susan Brickell is an Associate Editorial Director, leading news/deals commerce and strategy for Travel + Leisure. She has more than a decade of experience writing and editing fashion, beauty, lifestyle, health, travel, and home decor content for print and digital publications.

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Travel + Leisure / Susan Brickell

I’ve been a gear editor for more than a decade, meaning I’ve had my hands on hundreds (and perhaps thousands) of travel, activewear, and outdoor items — putting them to the test at home and on the go everywhere from America’s national parks to the coastlines of the Balearic Islands to the peaks of Nepal.

One of my favorite perks of my job is attending annual outdoor showrooms where I get to view all of the newest products launching to market in the next season. It was at a 2022 showroom that I set my sights on trying out the Hydro Flask Slingback Bottle Pack, and now that I’ve spent a year testing it, I just can’t help wanting to sing its praises to my friends, family, and the Internet. It may only have 85 ratings at Amazon, but it is a seriously underrated travel bag, in my opinion.

I took it on a five-day trip to Maine with my mom, where I wore it on some shorter hikes in Acadia National Park, as well as bopping around Bar Harbor. I used it for a week-long vacation in Thailand on urban adventures in Bangkok and for exploring Koh Phi Phi by foot and Thai longtail boat. It's been my travel companion on trips to the Blue Ridge Mountains outside of Atlanta, where I take my dog on day outings to nearby towns and woodsy walks. I pack it on almost any trip that I take.

Amazon

So what makes it so great? The Hydro Flask sling bag is made of 100 percent recycled polyester air mesh and features a durable ripstop lining, which makes it as tough as any of my hiking packs. Its compact frame measures ‎15.25 inches by 9 inches by 2 inches and weighs less than a pound, so not only is it incredibly lightweight to carry, but it also hardly adds any weight to my suitcase when I take it traveling.

The single sling strap lies securely and comfortably against my body when I’m leisurely exploring a city, and I can enlist the help of the stability strap if I'm moving quickly on a hike to ensure the backpack doesn’t bounce or slide around. I also find that the adjustable and stowable stability strap helps to more evenly distribute the weight of the bag when I’ve stuffed it to the brim — and it doesn’t feel awkward or rub my chest in an irritating way.

Susan Brickell / Hydro Flask

It has plenty of organizational features, with two exterior pockets, an interior padded tablet sleeve, and two internal stash pockets. In the larger pocket with the tablet sleeve, if I’m not storing my iPad to use on planes or train rides, I’ll stick other items that I want to protect in it, such as my journal, phone, or even my sunglasses, since the sleeve is lined with a super soft material. In the slightly smaller pocket on the front, I’ll stash my keys, wallet, sunscreen, snacks, and other small essentials.

My favorite feature, by far, is the pouch at the front that can hold up to a 32-ounce, wide-mouth water bottle — so I can bring my favorite Hydro Flask with me while I commute, cruise a new city, walk my dog, or tackle a short day hike. You can see in the below photo how it easily fits the water bottle, and then you just pull the flap with the brands label on top of the cap of the bottle to conceal it — you wouldn't even know I had a water bottle in there!

This sling bag is the perfect size — larger than a fanny pack or purse when I’m going to be out of the house or hotel for the day but small enough that I don’t have to carry a cumbersome hiking backpack with a multi-liter reservoir with me if I’m only walking a couple of hours. This one holds the perfect amount of water so I stay hydrated and prepared with all of my essentials for an afternoon.

Susan Brickell / Hydro Flask

But I’m not the only fan — this small but mighty sling backpack has earned a 4.6-rating from lots of happy buyers. One shopper that called it the “best sling ever wrote, “I’ve had the Patagonia 8-liter and the Kavu, and this Hydro Flask sling beats them both. It has a place to hold a water bottle, an additional strap to keep the bag from moving (that can be tucked away when you don’t want to use it), and a much better pocket set up.”

A traveler echoed the same sentiment, hailing it as the “best daily bag.” They said, “I purchased this for a trip, but it quickly became my daily purse. I keep my 22-ounce trail series in the front pocket, and I have a fairly large wallet inside with car keys and [a] small pouch of mom supplies.” They also pointed out that “the second strap is fantastic when getting in a face paced walk and for short hikes when I don't need much.”

Another customer expressed that it’s much “roomier than you think,” sharing that they “used this as my day bag in Costa Rica, as well as a trip to Disneyland.” They complimented it as being “fantastic” since it “honestly fits so much, plus my 25-ounce Hydro Flask.”

Susan Brickell / Hydro Flask

The bottom line: If you’re searching for a lightweight and comfortable sling bag that’s perfect for travel days, vacation outings, short hikes, and daily errands, look no further than the Hydro Flask Slingback Bottle Pack. I am so happy that I stumbled across this compact backpack as it’s become a travel bag I find myself constantly reaching for, whether I’m getting to know a new city or getting some steps in on an easy hike.

And thanks to its small size and being featherlight, I can conveniently slip it inside of my carry-on, personal item, or checked bag for longer trips when flying without it taking up precious packing space or triggering an overweight fee at check-in. While the $60 price tag may not make it the most affordable sling bag on the market, its durability, comfort, plethora of pockets, and water bottle pouch make it well worth it.

Amazon

At the time of publishing, the price started at $60.

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