Hike Journal - Kilauea Iki

by Lisa Frein, 2003
Kilauea Iki is a collapse crater adjacent to the main summit caldera of the active volcano, Kilauea. Beginning in August of 1959, geologists at the Hawaiian Volcano Observatory began detecting a swarm of deep earthquakes on seismographs located at the observatory. By early October, measurements indicated that the summit of Kilauea was beginning to inflate with new magma. From mid-September to November 1, more than 1,000 earthquakes were being detected. By November 14, all the activity beneath the surface had increased tenfold indicating that magma was making its way to the surface. At 8:08 p.m. that same day, an eruptive fissure broke through the south wall of Kilauea Iki Crater. Continuous fountaining occurred from a solitary vent located on the crater wall about 20 m above the small west crater of Kilauea Iki.

The lava rapids were described as “a bright orange, incandescent, twisting ribbon that made a slurred gurgling sound as it glided past. At the bottom of the cascade a stationary wave of lava, similar in appearance to a standing water wave in rapids, crested 1 m above the sluggish river and disappeared beneath the frozen crust of the lake.”

The lava fountain reached heights of 60-80 m by morning on November 17, and cinder, spatter, and pumice were falling onto the south rim of Kilauea Iki Crater. The falling fragments began to build a new cinder cone, which was eventually named Pu’u Pua`i (gushing hill).

A total of 71 million m³ of lava was ejected during the month long eruption, however because of all the drainbacks only 8 million m³ of lava actually remained in the crater when the eruption was over. The eruption stopped on December 20, 1959. For a more detailed description of the eruption please see: https://hvo.wr.usgs.gov/kilauea/history/1959Nov14/


I begin my venture on the Kilauea Iki trail at the Kilauea Iki Overlook where I can see what I am about to experience. Below me is a barren caldera floor covered by lava flows. I can see what looks like ants walking across the floor, but are actually my predecessors for this 4 mile hike. Taking time to understand what awaits me below, I learn of the 1959 eruption on Kilauea Iki that gave birth to the smooth, sometimes disrupted lava floor and the layers upon layers of hardened lava just covering a still liquid center.

Into the Rainforest:
Opting to go against the flow, I head to the left and begin my decent down 400 feet through rich rain forest with a very tropical feel. At almost any point along the beginning of the trail I can look to my right and see the caldera floor and then to my left and see lush rain forest. It looks like they have basically taken two different climate zones and stuck them side by side for my enjoyment.

On the way down, there is an abundance of ferns known as the hapu’u pulu distinguished by their three feather-like divisions or tri-penate formation. And of course, I am surrounded by the `ohi’a, the most abundant tree in the forest, holding on to its red lehua blooms. There are several bends in the trail helping me to make my way down to the caldera floor. There are also benches provided which I will make use of when ascending back to the top of the trail. Every detail of a tropical rain forest seems to be duplicated magnificently here that I almost forget I am on top of a volcano. Birds: There are songs of birds surrounding me like the ‘apapane (Hawaiian honeycreeper) feeding on the lehua and the `i`iwi (another type of Hawaiian honeycreeper) named for its song.
Across the caldera floor:
As I reach the bottom of the trail leading to the caldera floor I can begin to see the difference in landscape and feel the difference in climate. From walking through cool wet land, I now enter hot, dry, windy land. And as the vegetation lessens, the surface hardens. Stepping onto the caldera floor means a mile hike across a hardened lava flow from 1959, 21 years before I was born. It amazes me to see the rippled land from the pahoehoe flows. I imagine this is what the ocean would look like if frozen in a few seconds.

But what amazes me more is to see a tree, the prevalent ‘ohi’a, growing in one of the cracks still holding on to its beautiful lehua flower. Taking a step back, I look up to see the lush forest I just left and the rim of this caldera I was on top of moments ago. I feel like I have gone from person to ant as I know that’s what I look like from above.

Continuing my trek across the caldera, I see puffs of smoke coming up from the ground. On a closer look, I see steam vents, small holes with steam coming up from the ground, proof that the ground beneath me is still cooling off.


Pu`u Pua`i:
The massive hill, Pu`u Pua`i, to my left reinforces my feeling of being an ant. As windy as it is on the caldera floor I can easily see how such a massive hill was formed downwind from the vent during the lava fountaining in 1959. That same vent, the source of the lava I’m crossing, is now being choked by its own ejected material as cinders and ash from Pu’u Pua’i fall back inside the throat of Kilauea Iki.

What looks like smaller hills are also found on the caldera floor. These seem to have been formed by the crust being pushed upward as still fluid lava flowed beneath it.


There is a faint path to follow across the caldera floor where many visitors have walked before me and many will walk behind me to see the incredible life of Kilauea Iki. As you walk along this path to ascend back up the cliff, another type of vegetation is thriving in the cracks of the crater.

‘Ama’uma’u or ama’u for short is another fern similar to the hapu’u, except it is bi-penate meaning it has only two feather-like divisions. Another difference is the red color fronds of the ama’u when growing into adulthood. Many believe the red fronds are a result of a fight between Pele (goddess of the volcano) and Kamapua’a (half man, half pig). Kamapua’a was trying to put out Pele’s fires with his rain, but when retreating back into the forest to turn himself into a fern he was hit in the back of the head with Pele’s fire ball, thus the fronds are red. But as a constant reminder to Pele that she cannot get away from him, Kamapua’a always plants himself on her lava flows


Ascending to the top:
Making it across the caldera floor, I’ve now reached the hardest part of my hike, back to the top. Steep steps await me along with an immediate change of landscape full again of vegetation and signs of life. No need to get on the stairmaster tonight. But I think the view going back up is even more amazing. You get a true feeling of the richness of this forest.

It can get a little tricky on this side because several other trails intersect at a certain point, but following the signs and taking right turns keeps me on the right path. And now I have a better idea of where I am and what trails to take next time.


I stop to notice the boulders along side of the trail, bringing me back to the reality that this was the site of a volcanic eruption with rockslides and all. As beautiful as it is today, I would not have wanted to be here in 1959. Here I take full advantage of the benches provided. As I make my way back to the top I see the overwhelming amount of non-native ginger taking over the forest floor. I also see why the park is working to remove it so that the natural beauty of Hawai’i can shine through.

Back at the top:
Finally I reach my starting point, finishing my four mile loop. With a sense of accomplishment, I also have a new found respect for the land; its past, its present, and what it could do in the future


Last updated: October 5, 2018

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