an otherworldly adventure to the top of the largest volcano in the world
Mauna Loa Trail Guide
MAP: Trails Illustrated
PERMITS: required: $10 per trip, plus National Park entrance fee. Backcountry permit must be picked up in person 24 hours prior to your hike. Reservations can be made up to a week in advance by calling 808-985-6178
DESIGNATION: Hawaii Volcanoes National Park
BEST SEASONS: year-round – fall and spring reportedly best
DISTANCE: 43.4 miles round-trip, includes summit and Mauna Loa Cabin
WATER: only via catchments at Red Hill Cabin and Mauna Loa Cabin
ELEVATION: trailhead 6662ft – summit 13,677ft – gain 7,015ft
ACCESS: paved roads to trailhead
DRIVING: From the town of Hilo, drive west approximately 30 miles to the Kilauea Visitor Center. Drive west about 2.5 miles on Route 11, and turn right onto the Mauna Loa Road. Drive for 11.5 miles up the windy, single lane and park at the road’s end. Trailhead is at the Mauna Loa Lookout picnic area.
GUIDEBOOK: Hawaii The Big Island Revealed
WARNING: Hiking on Mauna Loa is a strenuous adventure to the summit of a serious mountain. Despite the tropical locale, snowy conditions and hypothermia are always possible. Stay hydrated and be conscious of your vulnerability to altitude sickness, or acute mountain sickness. Be prepared!
How to Hike to the Summit
This page primarily describes a strenuous backpacking trip up the Mauna Loa Trail.
Four days is recommended for this trek, which entails over 40 miles of hiking over mostly hard rock at high elevation, gaining over 7,000 feet along the way!
The primary Mauna Loa Trail technically ends below the top of the mountain, where it splits into the Summit Trail (to the summit) and Cabin Trail (to Mauna Loa Cabin – shelter). Each of these shorter trails are slightly more than 2 miles, one-way.
There’s two other approaches up the mountain – the Ainapo Trail and Observatory Trail.
The prehistoric Ainapo Trail is the hardest and least-used trail up the mountain. The summit is reached via a short and steep 15 miles (one-way), with over 8,000 feet of elevation gain.
The trailhead for Ainapo is accessed via a 4wd road through private property at Kapapala Ranch. A gate is kept locked and you must call the ranch to obtain the ever-changing code. The ranch asks for you to call 808-928-8403 between 7:30 and 8:30pm to make arrangements the night before your hike. The Halewai Cabin and Mauna Loa Cabin are available for backcountry shelter along the way.
Backpacking is not the simplest way to climb the mountain.
It’s more simple (But still a serious endeavor!) to hike the Observatory Trail, which is doable as a long day with a round trip of 12.8 miles.
The trouble with this approach is that your body has little opportunity to acclimate to the elevation.
The Observatory Trail begins from a trailhead at the Mauna Loa Observatory, approaching the mountain from the northeast (A significant distance from the heart of Hawaii Volcanoes National Park). It’s a rough road to the trailhead, but passenger vehicles are generally okay.
The trail along the road shortly before reaching the observatory. It will be on the right side of the road, as you’re heading uphill.
The first section of trail is a rough 4×4 road, which extends for a half mile before the true trail breaks off to the left. The rest of the way will be marked with large cairns (called ahu in Hawaii).
Along the way you’ll intersect a handful of old trails and roads – your Observatory Trail is the main boulevard through here and should be simple to follow. Eventually you’ll reach a junction with the Summit Trail. Turn right to access the summit, or go left for the Mauna Loa Cabin and other trails.
The Observatory Trail can also be backpacked, but an overnight permit must be obtained through Hawaii Volcanoes National Park.
Mauna Loa Trail Maps
Here’s a couple of maps published by the National Park Service that show these trails on Mauna Loa. Check out Trails Illustrated for a beautiful paper map of the National Park.
The best guidebook available for anyone visiting the Big Island of Hawaii (Backpackers, beach-goers, etc. you name it) is Hawaii The Big Island Revealed.
The Mauna Loa Trail
The Mauna Loa Trail is the best way to have a full adventure up the volcano. The trailhead is accessible via paved roads, and two backcountry shelters with water are available for overnight use.
Getting a Permit
Permits must be obtained from Hawaii Volcanoes National Park. Reservations can be made up to a week in advance of your hike (call 808-985-6178). After your phone call, the reservation will be payable here at Pay.gov.
Your permit must be picked up in person at the park’s Visitor Center, no more than 24 hours prior to your hike. There’s a flat fee of $10, in addition to the park entrance fee.
Mauna Loa Trail Description
Mauna Loa Lookout (mile 0) to Red Hill Cabin (mile 7.5)
This 7.5 mile distance is a great first day for those backpacking to the top of Mauna Loa. The Red Hill Cabin lies at an elevation of 10,035ft, and you’ll gain 3,373ft to reach here on your first day. Spending a night here is a great way to acclimate as you make your way up the volcano.
The cabin in Hawaiian is called Pu`u`Ula`ula, which translates as Red Hill. It is fully enclosed, and has 8 bunks. A water catchment system is located outside, and serves as the only reliable water along the Mauna Loa Trail until you reach the summit cabin. There’s also a composting toilet.
An original cabin was built here in 1914, torn down and replaced in 1996. When spending the night here, be sure to climb the hill and take in the views. The eruption that created this oxidized red hill is thought to have occurred about 8,500 years ago.
Red Hill Cabin (mile 7.5) to Summit Trail Junction (mile 17.0)
Pukauahi (as labeled on some maps), is encountered about 2.5 miles after leaving Red Hill Cabin. This is some reddish splatter and a cone from a prehistoric eruption. Pukauahi means smoke hole, but may have evolved from a similar word that means fire hill.
After hiking 4 miles from the Red Hill cabin, you’ll come upon the signed “Dewey Cone.” The cone was formed in an 1899 eruption and is named for US Admiral George Dewey, who won a decisive battle in the Spanish-American War at that time.
5.2 miles beyond Red Hill Cabin (and 1.2 miles after Dewey Cone) you’ll reach the “Steaming Cone,” formed from an 1855 eruption.
Less than half a mile later you may encounter a signed “water hole.” This is not recommended for drinking (and is most often frozen), but water is water.
“Pohaku Hanalei,” labeled on some maps, is 7 miles from Red Hill Cabin. This is more “prehistoric splatter,” and an old sign and benchmark here were covered by 1984 lava flows.
At 9.5 miles from the Red Hill Cabin you’ll reach a geologic feature called the North Pit, and the junction with the trail to Mauna Loa Cabin. For backpackers spending the night at the cabin, you can continue there for the night, or drop your pack here and hit the summit.
Trail Junction (mile 17.0) to the Mauna Loa Cabin (mile 19.1) via Cabin Trail
From the aforementioned junction, it is 2.1 miles to reach the Mauna Loa Cabin. Similar to Red Hill, the cabin has 12 bunks, a water catchment system, and a composting toilet.
A fitful night’s sleep is common here, in the thin air at an elevation of 13,250ft. If you find yourself especially restless, it’s certainly worth the trouble to bundle up, step outside, and view night sky.
The historic Ainapo Trail descends from the cabin to the south.
Trail Junction (mile 17.0) to the Mauna Loa Summit (mile 19.6) via Summit Trail
Likewise from the main junction (technically the end of the Mauna Loa Trail), it is 2.6 miles via the Summit Trail to reach the top of Mauna Loa.
A short way up this Summit Trail is where you’ll encounter yet another junction – the upper end of the Observatory Trail.
The summit is essentially the high point of the ridge that borders the west end of the mountain’s main crater, or caldera.
The caldera is called Moku’aweoweo. It is 2.7 miles long, 1.6 miles wide, and up to 600 feet deep. Be careful on the edge!
Magma sits deep somewhere beneath this weakness, causing the mountain’s original summit to collapse within the crater. Additional weaknesses, called rift zones, extend from here to the sea.
Mauna Loa is said to be the largest volcano in the world.
Rising 13,679 feet above the sea, its mass makes up the greater part of the Big Island of Hawaii, rooted from the bottom of the Pacific Ocean. Its total volume is estimated at 18,000 cubic miles. Mauna Loa is big.
In Hawaiian the name literally means “long mountain.”
Hawaii is a spiritual place, humming with the rhythms of the natural world. It’s the most isolated island chain on earth, born of fire and ash.
Most travelers will sooner or later hear about the fire-goddess Pele, most prominent from the ancient legends. It’s said that you’re not supposed to take any rocks from the islands or else you will suffer the wrath of “Pele’s Curse.”
The legend goes that Pele was fleeing from a feuding goddess, Na-maka-o-kaha’i, the goddess of the sea. Pele first landed on Kauai, but Na-maka-o-kaha’i continually flooded her out, from island to island, until she landed on Mauna Loa, on the Big Island. The ocean’s waves couldn’t reach her high on the mountain, so Pele made her first home in Hawaii on Mauna Loa.
So Mauna Loa is a virtual epicenter of all of Hawaii’s wild spirituality.
Native Hawaiians had climbed Mauna Loa for centuries – to leave offerings for Pele.
The first non-natives exploration was made by John Ledyard, on Captain Cook’s expedition in 1779. He attempted to go up the mountain, but failed in reaching the summit.
Archibald Menzies was the first non-native climber to have success in reacing the main crater, via the Ainapo Trail in 1794.
Charles Wilkes climbed Mauna Loa in 1840 with a large expedition, spending almost a month mapping the mountain and its craters.
Geology & Eruptions
Mauna Loa is classified as a “shield volcano,” meaning in simplest terms that it has gentle slopes created from numerous lava flows. It is so big and rises so gradually that it’s often difficult to discern it as a “mountain” from the surrounding landscape, though it rises over 30,000 feet from ocean floor.
The volcano’s most recent eruption was in 1984. In this event, lava first shot out from the southwest corner of the summit crater, extending throughout the rift zones. The eruption lasted for 22 days, and many sections of trail on the mountain pass over the remnants of its flows.
The mountain is certainly still an “active” volcano. USGS researches guess that over the course of the last 3,000 years, the mountain has erupted an average of once every 6 years. Considering that the most recent eruption was in 1984, it’s overdue for another one!
My Trip Notes and Photos
Day One: Mauna Loa Lookout to Red Hill Cabin
It’s a long and winding road to the trailhead at the Mauna Loa Lookout (Actually it’s only about 14 miles but who’s counting). It twists and turns, gradually narrowing into a single lane.
Most of the way was lined with tropical trees, and various exotic birds could be heard in the forest. Hawaii.
The morning was sunny and blue.
The forest gave way to a bright, stark, rocky expanse of volcanic terrain.
Some flowers, shrubs, and stunted trees managed to survive here, but soon even those would disappear.
All of the landscape throughout this hike could only be described as surreal, like walking on Mars.
A strange, disturbing rumbling sound was occasionally heard in the distance.
When we got our permit, the Park Ranger took my phone number for emergency purposes. He said we would get service on the mountain, and to periodically check my phone for emergency messages.
There were no messages, so we walked on.
Hmm, maybe it’s “normal” to hear rumbling sounds on Mauna Loa, but if that were the case, you’d think the ranger would have mentioned that, given his extensive list of other warnings.
still no messages
We reached the Red Hill Cabin in mid-afternoon, and settled in for the night. There was plenty of daylight left, so we had some time on our hands.
Regardless, it was a good idea stay here and acclimate to our new-found elevation of 10,000+ feet.
The cabin was cozy and shielded us from the cold wind.
An eerie wall of clouds had threatened an oncoming storm for most of the day, but the wind seemed to be blowing against them and holding them at bay.
In the evening we walked to the top of the nearby Red Hill.
Day Two: Red Hill Cabin to Mauna Loa Cabin (And Summit)
Throughout the morning we passed several formations like “Pukauahi,” Dewey Cone, Steaming Cone, and Pohaku Hanalei.
Mauna Kea is often seen prominently on the horizon to the north.
This is the summit, actually a high point along the rim of the main crater, called Moku`aweoweo. It’s two-and-a-half miles long, one-and-a-half miles wide, and 600 feet deep.
After some time on the summit, we returned to the fork in the trail, grabbed our heavy packs, and turned toward the Mauna Loa Cabin.
Day Three: Mauna Loa Cabin to Red Hill Cabin
We had a relaxing morning at the cabin, slow to get up and get started. Noah, a fellow hiker we met on the way, had the possibility in mind of going all the way back to the trailhead today. So he was up and gone early.
We enjoyed our usual tea and coffee.
The day was enjoyable and all downhill, coasting down the mountain to Red Hill.
We arrived at Red Hill early in the day, with plenty of time to get all the way back to the trailhead, if we so desired. We stopped and considered our options, but chose to stay the third night here at Red Hill as planned.
It was great to spend the day just hanging out in this cozy and unique place. Noah had pressed on, so we had the cabin all to ourselves.
Some late afternoon clouds moved in, seemingly out of nowhere.
Day Four: Red Hill Cabin to Mauna Loa Lookout
The morning was thankfully clear and empty of snow.
We had an enjoyable stroll back down to the trailhead, getting to our rental car with plenty of time left in the day to unwind, unpack, eat, shower, do laundry, and all the typical post-hike routines.
The Pacific Ocean was visible from the lower slopes of the mountain, blending in to the blue sky beyond the clouds.
The disturbing rumbling sound resumed on this final day. Later we asked a ranger about the sounds:
“Oh, they must have been shooting at the artillery range out there!”