Mauna Kea Humuula Trail

Mauna Kea/ Humuula Trail - Hiking Trail That Climbs the Tallest Mountain in the World
The Bottom Line:

Mauna Kea Humuula Trail is an incredible but challenging hike that will take hikers to the summit of the tallest mountain on earth! You'll want to bring plenty of water and layers for this trip, however, because the route is long, steep, and cold. 

- The HawaiianIslands.com Local Expert Team

If you or members of your vacationing party like unique travels and being able to say you conquered the tallest, longest, hardest, etc. of something, then one adventure you should strongly consider is the Mauna Kea Trail, also commonly referred to as Humuula Trail, is an energizing hike that will take you to the summit of the tallest mountain on earth.

That’s right, you didn’t read that wrong. Mauna Kea is 1,116 meters taller than Mount Everest, it just looks shorter because much of its height lies beneath the waves. Yet, that doesn’t change the numbers! If you want to hike to the summit of the tallest mountain on earth, then what you want is the Mauna Kea Trail. This adventure has the added advantages of not needing a permit, not needing a guide, and not needing to spend over $50,000 for the journey. You can, in fact, do the entire trip in one day. But be aware that while hiking Mauna Kea is nowhere near as dangerous as hiking and climbing Mount Everest, there are dangers and this strenuous trail should not be undertaken by the unprepared.

The Mauna Kea Humuula Trailhead is located just north of the Ellison Onizuka Visitor Center. Most people will park at the visitor center itself and walk north on the Mauna Kea Access Road until they hit the Mauna Kea Humuula Trailhead, but it is also possible to park at or near this trailhead so long as you are not blocking cross-traffic. The sign itself will say “Mauna Kea Ice Age Trail.”

The trail from this trailhead marker to the summit of Mauna Kea will span 13.4 miles there and back. You can cut that distance in half if you only want to go one way, either hiking up and driving back down or driving up and hiking back down as there is a university astronomical research facility and observatory with parking located near the summit of Mauna Kea. Staying on the path is easy thanks to posted route signs every 500 feet.

Those looking to do the hike as a full round-trip one, expect to spend a full day doing so. The average hiker will spend between seven and ten hours hiking Mauna Kea, but it is possible to complete the journey in around five hours if you keep a very brisk pace. Over the entire course of the hike, you will experience an elevation gain of 4,986 feet.

The first part of the Mauna Kea Trail is among the steepest as climbs over a collection of looser stones and boulders. After this initial 1,000 feet, the incline will start to lessen and hikers will find themselves hiking over and around what locals call aa rocks. Aa rocks are from lava flows that have a very rough surfacing, in other words, sharp and rugged. The aa blocks during this part of the trail are fairly blocky, making them less treacherous than other areas, but you should be especially wary of your footing when making your descent back to the trailhead.

The aa rock will gradually make way to simply hardened earth. Expect a steep incline with switchbacks for the next 3,000 feet, until the Mauna Kea Trail joins with the summit road. Shortly after this, the trail forks with the left fork leading to the stunning Lake Waiau and the right fork continuing on to the summit. Once you take the right fork, you will continue on past the telescopes as the final summit trail is found to the right of the road to those facilities.  You will recognize it for having a sign with the depiction of a hiker.

Something to note before you continue on this final leg to the very summit of Mauna Kea. There are conflicting reports on whether hiking to the absolute summit is disrespectful. Certainly, most hikers will avoid standing at the very top of Mauna Kea as this is where a small altar has been placed, but there is nothing preventing you from continuing here. Others may choose not to complete the last part of the trail altogether. Overall, Hawaii has aimed to discourage excessive tourism at this location despite it being such a unique spot as the tallest mountain point in the world and so it is important to proceed with respect for however far you choose to go.

Also important to remember, bring plenty of water! Dehydration is a big concern at this altitude both due to the elevation and the sun! Steady winds are always present, and summit temperatures can get to as low as minus 10 degrees Fahrenheit. Check the weather before you go, wear layers, and otherwise dress appropriately to enjoy a fun adventure. Due to this chilly weather, the best time to undertake this hike is during the summer months.

Insider Tip:
Lake Waiau is worth the short detour. This is the highest elevation lake on the Big Island and one of the highest in the entire country of the United States. It’s small but its existence as a pool of bright blue water amidst a sea of red and grays is truly stunning.