Hike Journal By Phillip Hoglin

Mauna Loa Observatory Trail
November 21 & 22, 2008
By Phillip Hoglin

For some reason, in a corner of one of the many tourist booklets, I noticed a small passage on Mauna Loa Volcano during a business trip to Honolulu. Intrigued, I started researching how I might be able to squeeze in a hike up the volcano over a weekend, and over 21-22 November 2008 the opportunity arose to attempt the Mauna Loa Observatory Trail. It wasn’t entirely a coincidence that I happened to pack cold weather gear and after buying some supplies I left Honolulu for Hilo on a Friday afternoon.

This would be my second trip to the Big Island. The first was with a mass-tour group which spent way too much time satisfying their corporate sponsors at various Macadamia and Orchid outlets and nowhere near enough time in the National Park (by all accounts the tour companies are all the same). I was quite enthusiastic to get the chance to attempt some unfinished business, although why I chose Mauna Loa rather than some of the many hikes closer to Kilauea is still a mystery.

After reading through some other trip reports, I decided to drive up toward the trail-head and stay in a vehicle at the trail-head parking area for the night before the walk. It was dark when I left Hilo however the trip wasn’t too bad despite the horror reports I’d heard about the road (more on hiring vehicles later). It was the strangest sensation seeing stars in the rear-vision mirror and up ahead whilst also seeing dark silhouetted masses of lava flows on either side of the road. I was thankful to eventually see the red lights of the observatory tower, but it still took me another 20-25 mins to reach the parking area.
Mauna Loa Observatory Car Park
Having hiked at altitude previously, I knew I was susceptible to altitude sickness (Acute Mountain Sickness) and I knew all my personal symptoms. By the time I arrived my head was starting to pulse, but the only thing I had to do was sleep and by the morning, after a restless sleep, I was ready to start. I got myself sorted out and started the walk at 7am. I noticed there were no other people or vehicles around at all and the only thing I saw was a scientist arriving for work at about 6:30.

The weather forecast was bad and I had been watching the NOAA website closely for a few days before the walk. But on the morning all I could see was cloud above and below me, but not at my level, so off I started, with Mauna Kea watching me as I made my way along a track to the trail head. I had planned to move no faster than 1.5km/hr, which meant that I would be at the North Pit before lunch. In all honesty I could not have moved much faster anyway.

The scenery was nothing I’d ever seen before and I was amazed at how interesting the scenery consisting of nothing but lava flow could be. The complete absence of any obvious animal life was haunting and the only plant life was a white lichen-like covering in very small areas of crevices and gaps in the lava.

The trail is very well marked with ahu every 20m but I still wouldn’t attempt this without a topographical map. There are some very logical and perfectly distanced rest areas including a cave created from a broken lava tube (Figure 1) at just under 12,000; some track/trail junctions, and another human-enhanced shelter at the North rim of the crater.
Shelter Area
Shelter Area
The headaches kicked in again at about 12,000 ft which was fully expected. I’d been taking it easy so I wasn’t concerned. I would expect most people to suffer some form of sickness on the trail (even if it was only mild), especially since it would be normal to travel from sea-level to over 13,000ft in under 24hrs for this walk because there is only so long one could spend at the trail head before boredom kicked in. Although boring, I’d recommend a night at the trail-head otherwise driving from sea-level to start the walk the same day is asking for trouble.

The best form of management is to recognise the signs, and to know when your comfort and recovery level has been exceeded. Then you can make the decision to continue (slowly), stop for an hour or more, or head back down; unless you are one of those rare lucky people who can ascend without a problem. As I live at sea-level I would have been surprised (pleasantly) if I’d had no effects. Everybody who gets altitude sickness reacts differently, but a good self-diagnosis sign that you’ve gone far enough is when nausea starts and you feel like dry-reaching (others will notice incoherence, your breathing and that you don’t seem to be on the same planet). If this happens then you probably won’t recover after a rest and you will need to descend to be safe.

The clouds were closing-in on Mauna Kea in the distance and I figured it would only be a matter of time before Mauna Loa started to get covered. After another km the temperature noticeably plummeted another 5 degrees C as I started to experience wind for the first time. Although there are no steep sections, and no areas that need scrambling, there was definitely a point where it seemed like the gradient of the mountain decreased allowing the wind to race across it. I’d think this would be quite normal on Mauna Loa and protection from the wind in the form of a shamagh, muffs, or beanie is important.
Shelter Area near the North Rim
Shelter Area near the North Rim
Without a map there is no way of telling where the cauldron is because the slope of the mountain is so gradual and you don’t get to see the summit until you reach the rim. Glancing back to Mauna Kea gives a good idea of how far there is to go as it is just a little higher than Mauna Loa; but this is a little inaccurate. In the end, North Pit opens up before your eyes, begging your admiration. I arrived a little faster than anticipated as it was only 11am; the bad news was that sleet was just starting to hurl toward the ground.

I figured that with precipitation before noon, the outlook wasn’t going to be good for the afternoon. I had the choice of heading to the cabin for shelter, heading for the summit, or heading back down and enjoying the spare day in the national park. I decided I would walk a km across the pit, see if weather worsened, then make a decision. My head was in pain at this stage but there were no other altitude effects other than some indecisiveness.
Across the Caldera Floor
Across the Caldera Floor
After reaching the South side of an impressive vent I stopped for a rest and decided to head back down. I was only about 2km from the cabin and would have made it; but the chances of getting snowed-in overnight were high and I didn’t savour the idea of walking through a’a covered with snow. The following morning I was vindicated by the snow covered peaks of Mauna Loa and Mauna Kea but at the same time a little resentful I didn’t push on (the decision was still the best one for me as a solo-hiker).

I headed back down to the trail-head, which look under two hours (it would have been about three from the cabin or summit). By the time I was in the vehicle and had driven back to 8,000ft any sign of sickness was long gone, although I wasn’t about to turn around and try again!

As with other trip reports, I did not see anybody on the whole trail at all except for three guys at about 2pm just starting the walk. They were not well equipped and I hoped they were just on a day walk. As my next destination was the national park I decided to sign back in in-person rather than ring through.
Park Boundary Sign
Some Planning Notes

Backcountry passes are required for this walk and must be obtained from National Parks Service. The Observatory Trail is the only one they will issue on the phone and only the day before the hike. They were still reluctant to give me a pass and emphasised the weather forecast several times to me, the lady on the phone even made a note that she had told me of the risk, presumably for indemnity reasons. I reassured her that the minute it looked dodgy I was going to head back down and I was not in the mood to take risks (if I didn’t have a booked flight I might have a little less wary).

Getting a hire vehicle was a pain. Several hire companies did not allow their vehicles on the Saddle Road which passes between Mauna Loa and Mauna Kea and is the only way to get to the access road. One company said they did over the phone, and had a different policy on arrival. The same company then agreed to let me travel on Saddle Rd but not the Mauna Loa Observatory access road. After begging I was eventually allowed to take my vehicle there (but I’d have to cover cleaning costs).

With the trouble I had in getting a vehicle I was expecting a bad road however Saddle Rd is about as good as I have driven on anywhere (easily a 90km/hr 55mph road) and there is nothing wrong with the Mauna Loa Observatory Rd either. In fact, one of the scientists I saw along the observatory road drove a sedan. A lot of the road, which was one-lane, was good quality, but there was a long section with pot-holes. As I was driving at night I was only crawling along at 30-35km/hr (20mph) but I had no troubles. At no stage did I even cross over a dirt road, so I’m not sure what the problem with hire companies is, I suspect they have not been up there themselves for some time. I’d still recommend a 4WD drive just for elevation over the road and a more comfortable sleep at the trail-head.

Equipment is important on this trip. I filled a 30L pack easily. Don’t be tempted to try this in hiking shoes, you will need proper boots as the aha is like glass and there are enough sharp edges to slice your ankles with a small mistake. And one last thing… there is only one toilet on the trail itself.
Toilet not far from the North Rim
Toilet not far from the North Rim
Here is the complete list of what I took and wore:

30L pack
Sun Glasses
Water (7L)
Sleeping bag (rated below 0 degrees)
Thermal underclothes
Heavy jacket (waterproof)
Light jacket
LS pullover
LS shirt
First aid kit (focussed on cuts/abrasions)
Socks x 2
Sunburn cream
Toilet Paper and bag
Everything was waterproofed

Last updated: August 21, 2017

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