Half Dome Is 14 Miles of Trail and 400 Feet of Cable

Seven miles up from the valley floor, where the forest finally runs out of mountain, a ranger stands at the base of a granite staircase and asks to see your permit. Above them: Sub Dome, a steep flight of stone steps and bare slabs. Above that, the thing you came for — two steel cables running side by side up the last 400 feet of Half Dome's rounded shoulder, close enough together to hold one in each hand, bolted straight into rock that offers nothing else to hold at all.

The National Park Service puts the summit at 8,800 feet, nearly 5,000 feet above the valley you started in. An 1865 survey report — the words are usually credited to state geologist Josiah Whitney — declared the summit "perfectly inaccessible, being probably the only one of the prominent points about the Yosemite which never has been, and never will be, trodden by human foot." George Anderson, drilling eye-bolts up the same shoulder, stood on top in October 1875. The Sierra Club replaced his rotted rope line with steel cables in 1919, and the queue has been forming ever since.

• Trailhead: Happy Isles (Yosemite Valley shuttle stop 16)
• Round trip: 14–16 miles depending on route; 16.2 miles via the John Muir Trail both ways (NPS)
• Elevation gain: about 4,800 feet, topping out at 8,800 feet
• Time: most hikers take 10–12 hours; the NPS advises turning around if you haven't reached the top by 3:30 pm
• The cables: the final 400 feet, climbed between two steel cables — no permit, no passage past the base of Sub Dome
• Permits: 300 per day (about 225 day hikers), via a March preseason lottery and a daily lottery two days ahead on recreation.gov — $10 per application, $10 per person if you win
• Cables season: typically the Friday before Memorial Day until the day after the second Monday in October

Eight miles of warm-up

From Happy Isles the route follows the Merced River into its granite stairwell. The Mist Trail is the direct line: 317-foot Vernal Fall close enough to soak you in spring, then a second climb to the brink of 594-foot Nevada Fall, the two of them stacked into barely three miles of trail. (Through October 2026 the lower Mist Trail is under repair and open only Friday through Sunday and holidays, plus weekday evenings and early mornings — most Half Dome starts beat the 7 am cutoff anyway, and the John Muir Trail runs parallel as the all-week alternative.)

Above Nevada Fall the grade finally relents into Little Yosemite Valley, a mile of flat sandy river-bottom where backpackers camp and the last reliable water flows — the NPS recommends a gallon per person for the full hike, and everything from here up is carried. A ranger station sits near where the trail leaves the valley and starts climbing again: two thousand feet of switchbacked forest, the dome appearing and disappearing through the trees, until the trees quit at the shoulder.

Sub Dome, then the cables

The permit checkpoint sits at the base of Sub Dome because what's above it needs managing. First the stairs — steep granite steps and open slabs that would headline most hikes by themselves. Then the saddle, and the cables.

The system is simple: two steel cables on stanchions, a lane of bare granite between them, 400 feet of climbing to the summit plateau. Traffic runs both directions in the same lane, so the rhythm is the same as it has been for a century — grip, haul, wait for the descending party, repeat. Many hikers bring gloves; the NPS asks that you carry them back down, having weighed the alternative in "hundreds of pounds of rotting gloves" accumulating at the base.

The park's safety language is unusually direct. Nearly all fatal falls from the cable route have happened when the rock was wet. The summit is a dangerous place in a lightning storm, and afternoon build-ups are a Sierra habit — hence the 3:30 pm turnaround advice, and the standing instruction not to start up if storm clouds are anywhere near. The top also runs 15 to 20 degrees cooler than the valley. None of it is technical climbing. All of it is unforgiving of a slip, and the mountain does not care that you drew a permit.

How the lottery actually works

Yosemite caps the route at 300 people a day past Sub Dome — about 225 day-hiker permits and 75 for backpackers, who request theirs with wilderness permits. Day hikers have two doors, both through recreation.gov, both $10 per application plus $10 per person if you win (the per-person fee is refunded if you cancel by the night before, or if the cables never go up).

The preseason lottery is the planning route: applications open March 1 and close March 31, each covering up to six people and seven ranked dates, with results emailed in mid-April.

The daily lottery is the second chance, and it runs on a two-day clock: apply between midnight and 4 pm Pacific two days before your hike — Thursday for a Saturday summit — and you'll know by late that night. Rangers check permits at the base of Sub Dome, and the named permit holder has to be there with the group.

That's the whole system: ten dollars, a calendar, some luck. What it bought the mountain is a cable route that moves like a slow queue instead of a dangerous one.

No permit? The Mist Trail doesn't need one

Everything below the base of Sub Dome is permit-free, and that includes what might be the best waterfall walk in America. The footbridge view of Vernal Fall is 1.6 miles round trip; the top of Vernal via the Mist Trail's stone steps is 2.4; the brink of Nevada Fall makes a 5.4-mile round trip with 2,000 feet of climbing — a full, spectacular day by any honest standard. Little Yosemite Valley at 9.6 miles round trip buys you the quiet version of the canyon, after the falls crowds thin out.

And if the lottery keeps saying no: the same two lotteries run every year, the math resets every March, and Half Dome is not going anywhere. It has been holding out on people since at least 1865.

Where this series goes next

This is the second article in our series on America's signature day hikes, after Angels Landing and its chains — single-day routes that earned national reputations, told with the route traced over real terrain. Every mile of the line above is browsable on the Half Dome page on Outdoors, alongside the rest of Yosemite's trails.

Sources

• The 14- to 16-mile round trip gains about 4,800 feet; most hikers take 10–12 hours, with a 3:30 pm turnaround recommendation; the summit is 8,800 feet, nearly 5,000 feet above the valley — NPS, Half Dome Day Hike
• The two metal cables allow hikers to climb the last 400 feet without rock climbing equipment; nearly all fatal falls from the cables have happened when the rock was wet; the summit is a dangerous place during a lightning storm; pack out gloves — NPS, Half Dome Day Hike
• The cables usually go up the Friday before Memorial Day and come down the day after the second Monday in October; an 1865 report declared Half Dome 'perfectly inaccessible,' and George Anderson reached the summit in 1875 — NPS, Half Dome Day Hike
• Permits are required seven days per week when the cables are up; a maximum of 300 hikers a day (about 225 day hikers, 75 backpackers) are allowed beyond the base of Sub Dome, where rangers check permits — NPS, Half Dome Permits for Day Hikers
• The preseason lottery runs March 1–31 with results in mid-April; the daily lottery runs midnight to 4 pm Pacific two days before the hiking date; fees are $10 per application plus a refundable $10 per person — NPS, Half Dome Permits for Day Hikers
• Vernal Fall drops 317 feet and Nevada Fall 594 feet; footbridge 1.6 miles round trip, top of Vernal 2.4, top of Nevada via the Mist Trail 5.4 with 2,000 feet of gain — NPS, Vernal and Nevada Falls trail guide
• Half Dome via the John Muir Trail is 16.2 miles round trip with 4,830 feet of gain; the final leg ascends steep stairs and granite slabs up Sub Dome, then the cables; Little Yosemite Valley is 9.6 miles round trip — NPS, Yosemite Valley day hikes
• From July 27 through October 2026, the Mist Trail between the John Muir Trail junction and the top of Vernal Fall is open Fridays through Sundays and holidays, and weekdays only 3:30 pm to 7 am, during trail repairs — NPS, Yosemite current conditions
• George Anderson stood on the summit on October 12, 1875; the Sierra Club installed the steel cables in 1919; the 'perfectly inaccessible' line is attributed to Josiah Whitney's Yosemite Guide-Book — Yosemite Nature Notes 46(2)
• Route geometry: Mist Trail, John Muir Trail, Half Dome Trail, and cable route, © OpenStreetMap contributors (ODbL)

Keep reading

• Angels Landing: the permit, the chains, and the fin
• How John Muir Trail permits actually work
• Choosing the right trail difficulty

Hero photograph: Half Dome from Glacier Point, nearly 5,000 feet above the Yosemite Valley floor. by David Iliff, licensed under CC BY-SA 3.0.