Mauna Loa (13,679 ft)  by  Brian Schultz    Tuesday  October 10, 2006

Mauna Loa is the largest active volcano in the world and Hawaii's other thirteener, just slightly lower in elevation than neighboring Mauna Kea. I planned the trip well in advance to use frequent flyer miles. Being busy climbing throughout the summer and fall, little thought went into studying Mauna Loa's route details- I assumed it would be a simple walk-up, which it is if everything goes right, but that wasn't the case today. I managed to make an adventure out of the class 1 route.

I relied only on a vague trip report as I drove the saddle road (Route 200), easily finding the Mauna Loa turn-off across the road and slightly east of the Mauna Kea turn-off. If I'd read the book, which was sitting in my room in Hilo, I would've known the road from the saddle road to the trailhead was in poor condition and would've allowed more time to drive the 17 miles. The narrow winding road was full of potholes, took a full hour to drive, and made an already late start even later. Fortunately, skies were sunny and clear when I began at 9:30 AM at the well signed trailhead past the observatory. Roundtrip mileage from the observatory to the summit is 12.6 miles with a gain of 2,700 feet elevation.

The trail was unlike the one I hiked on Mauna Kea in 2002. Expecting a soft dirt trail, I wore walking shoes instead of boots and became worried when the trail became a weaving route over lava slabs. It's handily marked by large cairns to keep hikers on the safe slabs and off the brittle volcanic rock flanking the slabs, which I learned when I diverted from the route briefly and found fragile rock crushing under my steps. But the terrain is manageable, crosses a road several times, and for a stretch there is an excellent dirt trail when Hawaii Volcanoes National Park is officially entered. Views of Mauna Kea were quite nice and I made good time up the first four miles, reaching 13,000 feet at 11:50, and figuring to be on the summit in an hour.

When I reached a trail junction, I checked the sign but continued ahead on the Mauna Loa trail thinking this was the trail I should be on. An excellent trail but unfortunately the wrong one. Two miles later I collected the unintended bonus of reaching the cabin on the opposite side of the summit rim, and on the way back shortcutted under the rim to save time and discovered another reason why the route is marked by such large cairns and why one should be following them. The 1942 eruption on Mauna Loa created a fissure which the cairned route handily offers a short jump across, but I was off route and in terrain where the crack was wider. I looked down and couldn't see the bottom. Needless to say, I made a careful jump across.

After rejoining the summit trail finally at 1:50, the route continued up on much rougher terrain, crossed additional but narrower fissures, and I arrived at Mauna Loa's summit benchmark at 3:15 PM. Nice, but a point to my upper left looked higher so I hiked another 15 minutes to it, where both GPS and altimeter watch indicated that it was slightly higher. The rim views (photo 1, photo 2) were incredible but because of the late hour I only stayed briefly and departed for the benchmark at 4:00. Drifting fog made the cairns harder to spot below the benchmark but finally lifted and after returning to the three-way trail junction, I began my descent to the observatory under a late afternoon sun casting long shadows across the rocks. I tripped several times, cursing myself each time I fell down, and later jammed my foot badly on the brittle lava rocks when I stepped at a funny angle. I wished I'd worn my boots.

At 5:00 and with a soon setting sun, I really stepped up the pace but it was all for naught. Once it got dark it was pitch black and I still had a mile remaining with no visible cairns, let alone a path. My headlamp couldn't illuminate far enough to see the cairns so if I hadn't set a waypoint on the GPS at the trailhead, I would've been spending the night on the mountain. To keep the bearing, I had to slow to a snail's pace but knew I'd catch the road or the observatory eventually and was heartened later to see a red light flashing in the distance at the observatory. At 7:40 I finally met up with the road and was soon at my car. I did stop occasionally on the descent to look up at the skies and admire its millions of stars twinkling and arrived back in Hilo late enough that my B&B hosts were worried about me.

This was a fun hike and even though my day turned into a 16.6 mile roundtrip hike, everything worked out in the end. I'm glad I wasn't hiking when an earthquake hit later in the week.

Trailhead to summit- 6 hours 15 minutes

Summit to trailhead- 3 hours 40 minutes

Start to finish- 10 hours 10 minutes

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