What an iconic run this is. An all-day journey to the top of Half dome and back awaits those willing to put in the effort. Along the way, runners will revel in the beauty of two stunning waterfalls, pristine nature and awe-inspiring views.
Bring well broken-in footware with good ankle support and good traction. Some of the most common injuries Half Dome
runners suffer are blisters and ankle injuries; take preventative measures for known "hotspots."
Bring a headlamp/light.
Gloves with excellent grip are strongly recommended for the cables, people have had their bare hands rubbed raw. There will be portions of the cable where the granite is slippery (not from rain, this is an inherent property) and your boots will not be able to provide any traction so you'll be relying on your arms. Practice LNT princples, and pack out your gloves and trash.
The only treated water on the trail is available (summer only) at a drinking fountain at the Vernal Fall Footbridge (less than a mile from the trailhead). Merced River water is available up to Little Yosemite Valley, however you should treat this water by boiling, using iodine, or using a giardia-rated water filter. Drinking untreated river water may cause significant illness.
The 14-to-16-mile round-trip run to Half Dome
is not for you if you're out of shape or unprepared. You'll be gaining elevation (for a total of 4,800 feet) most of your way to the top of Half Dome
. Most would say the reward is worth the effort. Along the way, you'll see outstanding views of Vernal and Nevada Falls, Liberty Cap, Half Dome
, and--from the shoulder and summit--panoramic views of Yosemite Valley and the High Sierra.
Most people take 10 to 12 hours to run to Half Dome
and back; some take longer. If you plan on running during the day, it's smart to leave around sunrise (or earlier) and then have a non-negotiable turn-around time. For instance, if you haven't reached the top of Half Dome
by 3:30 pm, you'll turn around. Check for sunrise and sunset times before you run. Regardless, each person should carry a flashlight or headlamp with good batteries (runners commonly struggle down the trail after dark because they don't have a flashlight). Although the trail is well marked, you should be prepared with a good topographic map and compass and know how to use them.
Most people begin the run from Happy Isles
(shuttle stop #16), which is about a 1/2-mi from the trailhead parking lot or about 3/4-mi past Curry Village (where additional parking is available). Shuttle service doesn't begin until 7 am, so if you're arriving before that, you can run on the road to the trailhead.
Look for signs for either the JMT/Mist Trail
to begin your run. You can either stay on the JMT all the way to Half Dome Trail
for a longer but mellower run (4mi) or follow the Mist Trail
(this is the classic route up to Half Dome
, ~2.5mi). The Mist Trail
offers an up close and personal view of both Vernal and Nevada Falls but is steeper than the JMT. Both the JMT and Mist Trail
will eventually intersect at the compost toilets near Nevada Falls -- there will be clear signage indicating the path to continue onto Half Dome
The trail steadily climbs to the north-northwest through the forest for roughly a mile before turning west and then southwest toward Half Dome
. You'll eventually emerge from the tree-cover onto solid granite and begin ascending a steep series of switchbacks known as the subdome (before starting the subdome, a ranger will check for your permit, it is a federal offense to even enter the subdome without a permit).
The most famous part of this trail is the ascent up the cables. The two metal cables allow runners to climb the last 400 feet to the summit without rock climbing equipment -- the cables are held up by metal poles drilled into the ground at regular intervals, each pair of poles has a wooden plank attached to assist runners. It can take 45mins to climb the cables one way -- longer if it's crowded. Since 1919, relatively few people have fallen and died on the cables. However, injuries are not uncommon for those acting irresponsibly.
The Half Dome
cables usually go back up the Friday before Memorial Day (conditions permitting) and come down the day after Columbus Day/before the start of snow.
Tips while using the cables:
Do not attempt the ascent if:
- Take your time and be patient with slower hikers
- Allow faster hikers to pass you (when possible)
- Remain on the inside of the cables
- Storm clouds are in the area
- The ground is wet (the cables and rock become very slick when wet; most accidents on the cables occur during wet conditions)
- The cables are down for the winter (typically, from the day after Columbus Day until Memorial Day weekend) (Check conditions update for status and any available updates)
Black bears frequent Yosemite's Wilderness and are adept at grabbing backpacks from hikers and campers--during both day and night. Always keep your food within arm's reach (or on your back); never leave it unattended. If you see a bear
, act immediately to scare it away: make as much noise as possible by yelling. If there is more than one person, stand together to present a more intimidating figure, but do not surround the bear.
Squirrels, Steller's jays, chipmunks, and other animals also live along the trail; never feed them or allow them to get your food. Do not leave your pack unattended (e.g., at the base of the cables or while you take a swim or nap). Keep wildlife wild: respect them from a distance.
Improper food storage
and feeding of wildlife may result in a fine (up to $5,000).