We asked a professional guide about his favorite water bottles to take with him into the backcountry

A water bottle is an essential piece of equipment when heading out into the backcountry (BC). At BCs, where hiking and skiing are repeated and the activity level is high, water is essential. It's also a great way to replenish energy with sugar, or enjoy delicious soup or coffee during rest periods. So the question becomes, "What kind of water bottle is best?" There are several things to consider when choosing a water bottle, including not only heat and cold insulation, but also durability in cold weather, ease of use, lightness, and capacity. We asked some experienced professional BC guides what kind of water bottles they usually use and why

---

Choices that suit your time and purpose

The type of water bottles you should bring and how many you should bring with you into the backcountry will depend on factors such as the time of year you'll be in the mountains, the length of the tour, and the purpose of the tour. For example, if you're in the middle of winter, you'll want a hot drink to keep you warm on the snowy mountain. However, if it's a sunny, warm spring day, you'll sweat while hiking and get thirsty, and want a cold drink. Professional guides plan their tour itineraries in detail, knowing how much activity there will be that day, including climbing and skiing, and they adjust the drinks they bring to the mountains based on the time of year and weather conditions at the time of the tour

Commonly used for hydration only:

PLATYPUS | Platy 2L Bottle

What our favorite BC guides say

The water bottle is a Platypus 2L. It gets smaller as you use up the contents. It can also be used as a hot water bottle in emergencies. (Telemark School & Ski Guide Izumiya AK.T| Kenji Akutsu)

On hot days, I use the Platypus hydration system. (RIKI JAPOW GUIDE| Riki Nakajima)

---

It is chosen for its light weight

nalgene | Wide-mouth Tritan 1.0L/0.5L

Nalgene is a favorite among outdoor enthusiasts worldwide thanks to its high-purity plastic and airtight seal. Made in the USA with environmentally friendly saturated polyester resin, it prevents plastic odors from transferring to your drink. The bottle body is resistant to temperatures from 100°C to -20°C, making it lightweight and durable

The unique cap system completely seals the bottle without using any gaskets, making it easy to clean and hygienic

The 1.0L is Nalgene's most popular bottle. It's available in both wide-mouth and narrow-mouth varieties. It's widely used in a variety of situations, from outdoor activities to everyday use. Even the same wide-mouth Tritan 1.0L bottle comes in a variety of colors and graphics, making it fun to choose

◆Click here

What our favorite BC guides say

Place a 500ml Nalgene bottle in a thermos case and fill it with boiled sports drink.
Then, add a 500-1000ml THERMOS thermos. A thermos with a large cup, like the kind children use, is convenient. I think the heat retention is about the same, and it's cheaper. (Kuroda Mountain Guide Office| Makoto Kuroda)

I've been using a Tiger Corporation bottle (model unknown, 0.5L size) for over 15 years, and its heat retention hasn't diminished.
And then there's the Nalgene 1L bottle. It never breaks! (LOCUS GUIDE SERVICE| Kazuya Furuse)

I love using Nalgene bottles and THERMOS thermoses. I use the Nalgene bottle for oral rehydration solutions, etc. The wide-mouth 0.5L size is very convenient. I use the Thermos for hot water. In winter, I use the 0.75L Thermos. In spring, I use the 0.5L size. ( Rhythm Works | Ritta Asahi)

---

It is chosen for its warmth and ease of use

THERMOS | Mountain-specificbottle

This "mountain bottle" is designed for the harsh conditions of the mountains. Nicknamed "Yamasen," it has garnered overwhelming support from climbers and mountain guides. Its secure silicone body ring, shock-resistant bottom cover, and simple screw that's easy to use even with gloves on make it the ultimate in ease of use on snowy mountains

	FFX-901	FFX-751	FFX-501
capacity	900㎖	750㎖	500㎖
Heat retention*(6 hours)	Over 80°C	Over 78°C	Over 77°C
Cooling performance*(6 hours)	Below 9°C	Below 10°C	Below 10°C
weight	380g	360g	280g
price	￥7,150	￥6,600	￥6,050
Color	Available in three colors: Matte Red, Matte Black, and Matte Stainless Steel	Available in three colors: clear stainless steel, matte black, and sand beige	Available in three colors: sand beige, matte black, and clear stainless steel
Dedicated pouch	￥2,640	￥2,420	￥1,980

*The heat retention effect is the temperature of hot water when the product is filled with hot water up to the bottom of the middle cap at room temperature of 20°C ± 2°C, and when the water temperature is 95°C ± 1°C, the middle cap and cup are attached and the product is left standing upright for 6 hours. The cold retention effect is the temperature of water when the product is filled with water below 4°C up to the bottom of the middle cap at room temperature of 20°C ± 2°C, and when the water temperature is 4°C ± 1°C, the middle cap and cup are attached and the product is left standing upright for 6 hours

◆Click here

What our favorite BC guides say

Bottle: Mountain-specific bottle 900ml. Its heat retention is unparalleled. I put piping hot water in it. (Telemark School & Ski Guide Izumiya AK.T| Kenji Akutsu)

I love using Thermos Mountain Bottles, either 900mL or 500ml. They're consistently easy to use! (Vertical Land| Yuki Ito)

Mountain-specific bottle, 750ml. It doesn't get in the way even when placed horizontally in a backpack. (Tyrol| Iwao Saeki)

THERMOS 500ml. Its lightness, slim silhouette, and moderate heat retention are the reasons I love it. (COLOR SPORT CLUB| Tomohiro Shakawa)

The 350ml THERMOS is for tea, coffee, etc.
The 500ml mizu or 500ml Yamasen is for hot water only. (RIKI JAPOW GUIDE| Riki Nakajima)

THERMOS 0.5L bottle designed specifically for mountain use. The most reliable bottle in terms of heat retention. (Infield| Toyokazu Nakano)

THERMOS Mountain Bottle: Lightweight and easy to handle even with gloves on.
Reliable with its outstanding heat retention. (Bantei ~bamboo tail~| Yu Takeo)

THERMOS! Excellent heat retention. (Kagura Powder Station| Kazuya Igarashi)

I carry a THERMOS mountain-specific water bottle. Since I rarely drink from it myself on one-day tours, I keep it with me for emergencies. (Epic Japan| Akiko Nakae)

THERMOS! Trust and実績 (Daichi Terui)

A rival to "Yamasen" and also highly trusted for its heat retention

mont-bell｜ALPINE THERMO BOTTLE

This lightweight, compact thermos bottle, designed for mountain climbing, offers exceptional heat retention even in extremely cold environments. The exterior is made of durable SUS304 stainless steel, while the interior is made of exceptionally corrosion-resistant SUS316 stainless steel. Its silicone rubber non-slip grip and inner cap that opens and closes with a half-turn make it easy to use even when wearing gloves. You can choose between a direct-drinking version for quick hydration or an inner cap/cup version with enhanced heat and cold retention, depending on your needs

The 0.5L model was also awarded the OutDoor INDUSTRY AWARD 2016 WINNER at the OutDoor Show 2016, Europe's largest international outdoor trade fair

	BOTTLE 0.9L	0.75L BOTTLE	0.5L BOTTLE	BOTTLE 0.35L
capacity	900㎖	750㎖	500㎖	350㎖
Heat retention performance*(Starting temperature 94℃ → After 6 hours)	Over 81°C	Over 80°C	Over 78°C	Over 74°C
Cooling performance*(4°C at start → after 6 hours)	Below 70°C	Below 80°C	Below 8°C	Below 10°C
weight	380g	360g	265g	240g
price	￥4,950	￥4,400	￥3,850	￥3,300
Color	Available in two colors: stainless steel and red	Available in three colors: dark gray, red, and stainless steel	Available in four colors: dark gray, red, stainless steel, and green	Available in four colors: green, dark gray, red, and stainless steel

*The effectiveness of heat retention and cold retention is measured when the product is filled with the specified amount of 95°C hot water (4°C cold water) and left for a specified period of time (6 hours) at room temperature of 20°C (±2°C)

What our favorite BC guides say

I don't have any particular preference, but I use the Mont-bell Alpine Thermo Bottle 0.9L.
Whether it's Mont-bell or THERMOS mountain bottle, I recommend one with high heat retention for winter. (CIRCLE GAME guide service| Shohei Sasaki)

Mont-bell's Alpine Thermo Bottle 0.5L! Excellent heat retention. (Mountain Guide Coyote| Ryuta Furuichi)

I carry a Mont-bell 0.35 bottle and two THERMOS 0.15 or 0.18 bottles. The larger one is for emergencies (it cools down as it's constantly being used while hiking), and I don't use it until the end. For drinking, I only use the small bottle and a cold 500ml PET bottle. (Hokkaido Backcountry Guys| Satoshi Tsukahara)

---

I want to read this together!

Related reading

High-spec thermos water bottle put to the test in snowy mountains | Can you eat instant noodles piping hot on a mountaintop? This series attempts to test items that seem like they would make snowy mountain time and snow skiing more comfortable and enjoyable, and reports on their actual performance from a user's perspective...