Hawaii Volcanoes National Park High Point Trip Report

Mauna Loa (13,667 ft)

Date: December 26, 1992
Author: Bob Sumner

To get to the Mauna Loa dayhike trailhead from Kona, go northeast on State 190 about 35 miles to the Saddle Road, which is State 200. The Saddle Road is the most direct route from Kona to Hilo, but it is very narrow and winding. Accidents are common, so the rental car companies don't permit their vehicles on it. (Of course, no one checks this.) Go southeast on the Saddle Road for about 25 miles to Humuula Saddle at 6600'. To the left (north) is the road to Mauna Kea; one hundred yards further on the right is the unsigned road to Mauna Loa. Follow this poor paved road for about 17 miles to the U.S. Weather Observatory and the signed Mauna Loa trailhead. The elevation here is about 11,150'.

At 13,667', Mauna Loa is Hawaii's second highest mountain. It is a gigantic shield volcano, which means that lava doesn't shoot out in huge explosions (a la Mt. St. Helens), but rather flows out less violently creating a very wide enormous mountain.

Mauna Loa is an active volcano and still has occasional eruptions, though most of the lava activity is on the south side, down in or near the Hawaii Volcanoes National Park.

From the weather station, one can hike the long dirt road to the top, or the fairly direct hiking trail. The trail is about 13 miles round trip and 2600' gain. It is marked with cairns and ducks every 50 to 100 yards, and ascends gently sloping lava fields. Both kinds of lava are present: pahoehoe, which is black and has a smooth fluidic appearance; and a'a, which looks like glued jumbles of small very rough rock. There are actually two trails ascending the north slopes of Mauna Loa: they are parallel and are about 1/4 mile apart. Both are marked with ducks.

As I ascended there were large billowy storm clouds creeping up the slopes from Hilo. The wind increased steadily and by the time I reached the crater rim it was apparent things were going to get ugly. There was still more than a mile and several hundred feet to go. I was starting to slow down though; the altitude change from sea level to over 13,000' was catching up with me. Soon the clouds caught me and I continued through pea soup fog by following the ducks. Minutes later the wind gusted and the snow began. By the time I reached the summit it was a full-blown white-out. Signed the register and bailed - no views this time.

After descending 1000' or so, the weather lightened up. I discovered I was on the alternate trail in the lava fields, and that it rejoined the main trail a couple of miles from the trailhead. By 5:00 PM I was back in Kona sipping a mai-tai. It was warm and sunny there, while high above on the peak the clouds were swirling. The nasty weather continued throughout my stay. These "pineapple express" storms would pound Los Angeles a few days later.