TRAIL NUTRITION · THE REAL NUMBERS

The map sells you miles.
The mountain charges hours. ⛰️

A 5-mile hike sounds like a morning. Add 1,500 ft of climbing and it eats the day — and the food and water you didn't pack. Below, every big curated climb costed out in moving hours, litres and grams, plus the detail most pages skip: whether there's any water up there to refill from.

12Climbs costed from real trail data
11Of them with no water on the route
7h 45mHalf Dome — moving time alone
WHAT THE CLIMB COSTS

Your day, in hours, litres and grams

Distance and elevation gain come from our own curated trail data. The rest is arithmetic: climbing time by Naismith's rule, water by CDC heat guidance, food by the 30–60 g of carbohydrate per hour endurance range. Ranges, not verdicts — the low end is a cool day, the high end is July.

Climb Distance & gain Moving timeno breaks Water to plan Carbohydrate
⛰️ Half Dome Yosemite National Park 16 mi · 4,800 ft up 7h 45m 3.9–7.7 L 🎒 no refill on route 230–460 g
⛰️ Paintbrush Canyon–Cascade Canyon Loop Grand Teton National Park 19.9 mi · 4,480 ft up 8h 50m 4.4–8.9 L 🎒 no refill on route 270–530 g
⛰️ Bright Angel to Havasupai Gardens Grand Canyon National Park 9 mi · 3,040 ft up 4h 30m 2.3–4.5 L 💧 refill on route 140–270 g
⛰️ Emory Peak Trail Big Bend National Park 10.5 mi · 2,500 ft up 4h 45m 2.4–4.8 L 🎒 no refill on route 140–280 g
⛰️ Chasm Lake Rocky Mountain National Park 8.4 mi · 2,390 ft up 4h 2.0–4.0 L 🎒 no refill on route 120–240 g
⛰️ Grinnell Glacier Glacier National Park 10.6 mi · 1,840 ft up 4h 25m 2.2–4.5 L 🎒 no refill on route 130–270 g
⛰️ Sky Pond via Glacier Gorge Rocky Mountain National Park 9.8 mi · 1,780 ft up 4h 10m 2.1–4.2 L 🎒 no refill on route 120–250 g
⛰️ Forks of Cascade Canyon Grand Teton National Park 13.3 mi · 1,720 ft up 5h 20m 2.6–5.3 L 🎒 no refill on route 160–320 g
⛰️ South Rim Trail Big Bend National Park 12.5 mi · 1,700 ft up 5h 2.5–5.0 L 🎒 no refill on route 150–300 g
⛰️ Angels Landing Zion National Park 5.4 mi · 1,500 ft up 2h 35m 1.3–2.5 L 🎒 no refill on route 80–150 g
⛰️ Chimney Tops Great Smoky Mountains National Park 3.3 mi · 1,400 ft up 1h 50m 0.9–1.8 L 🎒 no refill on route 50–110 g
⛰️ Mount Washburn Yellowstone National Park 6.2 mi · 1,400 ft up 2h 45m 1.4–2.8 L 🎒 no refill on route 80–170 g

Moving time uses Naismith's rule (3 mph plus an hour per 2,000 ft of climb); water follows CDC heat guidance (~1 L per hour working in the heat, about half that when it's cool); carbohydrate uses the 30–60 g per hour endurance range (ACSM/ISSN). Moving time is exactly that — it counts no breaks, no photographs and no summit sandwich, so a party that stops will be out longer than the column says.

DATA · OUR CURATED TRAIL TABLE · VERIFY CLOSURES AND WATER AT NPS.GOV

WHAT GOES IN THE PACK

Six categories, and how to pick inside each

We don't name a favourite bar — brands change, and what works is the one you will still eat at hour five. So each block gives the one thing that decides it, and a search you can run yourself.

Electrolyte drink mixes

So a long hot day doesn't taste like punishment and you actually keep drinking.

Single-serve sachets, not a tub — and a flavour you already tasted at home.

Browse →

Bars, chews and gels

The 30–60 g of carbohydrate an hour from the table, in a form you'll still eat late.

Check what melts — chocolate coatings and a July canyon don't mix.

Browse →

Salty real food

The calories that don't taste sweet — which is why people stop eating on long days.

Salted, not candied, and resealable: an open bag empties into the pack.

Browse →

After the big day

Protein and easy calories for the evening after a long descent, and the morning after.

Something that mixes with cold water — hot water is a luxury at a trailhead.

Browse →

Sun, bugs and blisters

Not food, but it lives in the same pocket and ends more hikes than hunger does.

Blister tape goes on before the blister, not after.

Browse →

Fuel for small humans

Kids run out sooner and say so earlier — the only early-warning system you get.

Snacks they already like at home; a trail is a bad place for a new flavour.

Browse →

Some links on this page are affiliate links — if you book or buy through them we may earn a commission at no cost to you (disclosure). This page is informational only and is not medical advice: it is arithmetic over published planning rules of thumb for time, water and food. For anything involving altitude, medication or a health condition, talk to a doctor.

WHERE THE MATH CHANGES

Parks that rewrite these numbers

Heat and altitude move the ranges above — and in these parks our curation says so explicitly.

Arches National Park

Summer heat above 100°F

The park's own weather page states that summer temperatures often exceed 100°F, and the trails to Delicate Arch and Tower Arch have no shade at all. There is no drinking water on any route here — everything you drink starts in your pack.

Badlands National Park

No water on any trail, and no shade either

The park tells hikers to carry two quarts per person for a two-hour walk, and a gallon per person per day in the backcountry, where the little water that exists is too full of sediment to filter. The 10-mile Castle Trail crosses open prairie with nothing to hide under, and summer highs sit in the 90s°F.

Big Bend National Park

One liter per person, per hour

The park repeats the same instruction on every trail page: carry one liter of water per person for every hour you plan to walk. On the desert floor summer highs run past 100°F by late morning, and the Chisos run only 10–15 degrees cooler.

Biscayne National Park

Only one island has drinking water

Elliott Key has drinking water and cold-water showers, but the supply runs on a generator and NPS advises bringing your own in case it fails. Boca Chita has no drinking water, no electricity and nowhere to buy anything. There is no food or water for sale anywhere in the park — carry everything in. Informational only, not medical advice.

Canyonlands National Park

No water, no food, no fuel inside the park

<p>Canyonlands sells nothing. There is no drinking water on White Rim Road at all, and the park sets one gallon (about four litres) per person per day as the minimum for anyone out on it. Buy everything in Moab — including more water than you think the day needs.</p>

Grand Canyon National Park

Inner-canyon heat is the park's #1 danger

The canyon floor runs 20–25°F hotter than the rim — summer inner-canyon highs top 110°F. Electrolytes, salty food and a dawn start are not optional. Informational only, not medical advice.

Grand Teton National Park

Elevation adds up on the longer days

Jenny Lake sits around 6,800 ft and Paintbrush Divide tops 10,700 ft — hydration and pacing matter well before anything looks alpine. Informational only, not medical advice.

Joshua Tree National Park

There is no water anywhere in the park

No trailhead, campground or trail in Joshua Tree has a potable water source. Carry all the water you'll need — NPS guidance for desert hiking is roughly one gallon per person per day, more in summer heat. Informational only, not medical advice.

Rocky Mountain National Park

Altitude changes the math

Trailheads start near 8,000–9,500 ft and the alpine tops 12,000 ft — hydration, electrolytes and easy calories matter from day one, and so does pacing. Informational only, not medical advice.

Sequoia & Kings Canyon National Parks

Altitude at the groves, heat at the gates

Most sequoia groves sit at 5,000–7,000 feet, and the Rae Lakes Loop crosses Glen Pass near 12,000 feet — real altitude for anyone arriving from sea level. The opposite problem waits at the entrances: the foothills around Ash Mountain average near 97°F in July. Carry water for the elevation you're actually hiking at, not the one at the entrance station.

Zion National Park

Desert heat & sun exposure

Zion runs hot and exposed — summer canyon temps regularly top 100°F. Plan electrolytes, calories and timing, not just water. Informational only, not medical advice.

Want the list adapted to your park, season and party? The packing-list generator builds it — and emails you the PDF for the trailhead, where there is no signal.

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QUICK ANSWERS

Frequently asked

How much water should I carry for a big climb?

Plan by hours of movement, not by miles. Working in the heat takes roughly a litre an hour (CDC heat guidance); on a cool day about half that. The table on this page turns each curated trail's distance and elevation gain into a moving time first, then into that range — and tells you whether there is any water on the route to refill from.

Why does a short trail take so long?

Because climbing costs time that distance doesn't show. Naismith's rule, the standard for route planning since 1892, adds a full hour for every 2,000 ft of ascent on top of walking 3 mph on the flat. That is why a 5-mile hike with 1,500 ft of gain eats an afternoon.

How much should I eat while hiking?

Once you are moving for longer than an hour, the endurance range is 30–60 g of carbohydrate per hour (ACSM/ISSN). Split it across textures — sweet and salty — because most people stop eating on long days out of flavour fatigue, not hunger.

Is this medical advice?

No. This page is arithmetic over published planning rules of thumb for time, water and food. It is informational only and it is not medical advice — for anything about altitude, medication or a health condition, talk to a doctor.