Round Trip Mileage: 11.5 miles
Elevation Gain: 4500’
Gear: If you're traveling to the summit area of Mauna Kea, you need to equip yourself as you would for any major world summit of this altitude. Bring sturdy mountaineering boots, winter gear, and the ability to keep yourself alive on a high mountain at least overnight.
Permit Information: You don't need a permit to climb, but you do have to fill out a form at the Visitor Center and leave it in a drop box. There are no quotas per day and no fees.
- NOAA forecast for Mauna Kea's summit area at 13,000 feet;
- NOAA forecast for the Mauna Kea Visitor Information Center at 9000 feet.
- Mauna Kea Weather Center Current Conditions.
Map: Topographical Map of Mauna Kea
Overview: Superlatives abound when describing Mauna Kea: the highest mountain in the Pacific Rim; the tallest sea mountain in the world, rising 33,000 feet from the ocean floor; the highest lake in the Pacific Rim and the only alpine lake in Hawai’i; the highest mountain in the state of Hawai’i and the Big Island. Mauna Kea, literally white mountain, rises to an elevation of 13,796 feet above sea level and is comprised of many cinder cones near its summit. While there is a road to the summit (4WD) and several summit astronomical observatories on the summit, most of this mountain is untamed and wild. Hiking to its summit requires substantial effort and above average hiking skills, although the trail is relatively easy from a climber’s perspective. The entire upper portion of the mountain is owned by the University of Hawai’i, so there’s a bit of red tape to deal with here. When you arrive at the trailhead, which is the Visitor Center, you need to fill out a form and leave it in a dropbox in front of the building. There’s no need to actually speak to a Ranger before hiking. Just fill out the form and leave it in the box. Check in when you get down so they know you’re off the mountain.
Getting to the Trailhead: from either side of the island, take the Saddle Road, Hwy. 200, to the Mauna Kea road, between the 25 and 30 mile markers on the Saddle Road. The road is well-marked. From the turn, follow the paved road for six miles to the Ellison Onizuka Mauna Kea Visitor Information Center. This is the trailhead. It’s possible to drive to the summit, but where’s the fun in that? For more information about climbing Mauna Kea, read the Visitor Center's suggestions. The Visitor Center is open from 9am - 10pm every day of the year, but the restrooms are always open. The Visitor Center and the summit telescopes often offer programs for viewing the cosmos. Check their website for availability. Find out about Summit Road conditions.
The Hike: After dropping off your form at the Visitor Center, walk up the road for about 0.12 mile until you see a two-track 4WD road leaving from the left (to the west). Take this road for 0.25 mile until you intersect a trail departing to the right (north). This is the beginning of the Humu'ula Trail. Climb the relentlessly steep first 2000’ of trail and after about a half a mile, reach the boundary (unmarked) of the Mauna Kea Ice Age Natural Area Reserve. Once you reach the reserve, begin to look sharp for numerous archaeological sites along the trail. While these sites have received attention since the 1980s, a vast majority of these sites have not been evaluated by professionals. Take photos from afar and enjoy these sites from a distance. Leave no Trace.
Once you reach the 12,000’ mark, the terrain starts to ease a bit and you can begin to spot the summit cinder cone, identified by the road cutting across it. This part of the trail is otherworldly, with staggering colors and multiple cinder cones. You’ll likely be thousands of feet above the clouds below. Take a look toward Hilo -- it’s probably raining down there.
Persevere through the 13,000 foot mark and spot the trail to Lake Waiau. This short diversion is well worth your effort. Contained within the Pu’u Waiau cinder cone at an altitude of 13,022 feet, this lake is the highest in the Pacific Basin and the Big Island. The lake is very shallow, and is a site that is sacred to the Hawaiian people. Stay away from the lake and do not disturb religious offerings around the lake. Radiocarbon dating of samples at the bottom of the lake indicate that it was clear of ice 12,600 years ago. What feeds this lake? Permafrost trapped within the lava from the last ice age percolates out and collects in this basin. The reason why it does not percolate so easily into the lava rock like water does throughout the rest of the island is unknown. Two theories attempt an explanation: either sulfurous steam altered the volcanic ash to low-permeability clay soil; or explosive interactions between rising magma and water (phreatic eruptions) formed exceptionally fine ash that also would reduce the permeability of the lake bed. Regardless, sit and marvel at this lake sitting in such a dry, unforgiving place. This side trip is 0.16 mile one-way and about two hundred feet more elevation gain.
Continue past the trail intersection for Lake Waiau for 0.62 mile and reach the road. Ugh. After a quiet hike of solitude through an alien landscape, reaching this road is jarring. Quickly walk along the road for 0.84 mile and be very wary of rubber-necking drivers (ironically, this might be the most dangerous section of this “trail.”). There are a few places where it seems like you can leave the road and climb directly uphill, but you’ll just exacerbate erosion on these loose slopes. When you reach the summit area and can see the parking area, leave the road and hike 0.36 mile to the red-tinted summit cinder cone on a trail. Bask in the view. Look down your nose at the gawking “gasoline climbers.” Retrace your steps to descend.
Safety: There is no public transportation on Mauna Kea. Cell phones might work in some places, but you should not count on it. In general, your best bet for help is to hike due east toward the road and try to flag down a vehicle.
Even More: Mauna Kea offers some great tropical skiing possibilities. Didn’t bring your skis to Hawai’i? From December to around March each year, snow occasionally falls on Mauna Kea and Mauna Loa. Mauna Kea offers better skiing opportunities due to its steeper nature and due to the summit road, which is plowed to allow scientists to access the summit telescopes. Some locals use the road as a “lift” and ferry others up and down the mountain for runs. I’m a backcountry skier from the Rocky Mountains, and although I’ve never skied Mauna Kea due to timing, I’ve spotted several great runs given proper conditions. With backcountry touring gear, once could likely ski several 4000’ runs on several faces of the many cinder cones atop Mauna Kea. Avalanche danger is likely typically on the lower end because there isn’t much very steep terrain and the depth of the snow would make slabs manageable. Wet slides could be concerning on sunny aspects, especially with tropical sun.