Dispatches from the Road (the one I wish I was still on): The Nu'uanu Pali and a bit of Hawaiian History

It's been a few weeks since I was enjoying a visit to the Hawaiian Islands, and school has begun in earnest, but I had a few more dispatches that I hoped to complete before academic matters overwhelm me. We've visited Pillbox Hill, stepped over molten lava, searched for native bird species, found invasive species, and explored two kipukas on the Big Island. We explored one other trail, the Old Highway on the Nu'uanu Pali near Highway 61 where it passes through the Ko'olau Range between Honolulu and Kailua. It's a place of mysterious stories and tragic history.

There's a movie and TV trope called the Fallacy of the Climbing Villain. In a chase scene, the person being chased has a choice of going downstairs or upstairs. They invariably choose to go up, which invariably leads to them to being trapped or plunging down to their deaths. It's a sign of weak scriptwriting skills most of the time. On the other hand, there are moments in real life when one has no choice. In the first years following European contact with the inhabitants of the Hawaiian Islands a momentous event was unfolding. For the first time in Hawaiian history the islands were being united under one king, Kamehameha I. This unification was not a voluntary exercise; the kings and chiefs on the various islands were not willing parties to the idea, and a series of violent invasions were needed to subdue each of the main islands (with the exception of Kaua'i. The king of Kaua'i got smart and acquiesced after seeing what happened to everyone else).

On Oahu in 1795, things weren't going well for Kalanikūpule and his army. Kamehameha drove Kalanikūpule's soldiers up the Nu'uanu valley, and they soon found themselves trapped between the forces of the invader king and the 1,000 foot Nu'uanu Pali. A few tried to climb down, but more than 300 were driven over the edge, plunging to their deaths (hundreds of skulls were found at the base of the cliff during road construction in 1898). The remaining forces surrendered and the invasion of Oahu was complete.
Plenty of other stories abound about mysterious beings around the Pali. There are tales of the goddess Pele (we heard one of them from our waitress at a restaurant in Kona) appearing as a woman hitchhiker. To this day, travelers on the highway carry gifts for the gods as they drive over the pass.

In 1959, tunnels were bored through the cliffs to build a modern thoroughfare, and the old narrow Pali Highway was abandoned to the elements. It serves today as a trail that provides spectacular views of the Pali cliffs and the lowlands of the ancient Ko'olau caldera that now is covered by the towns of Kailua and Kane'ohe. It's a wonderful stroll that provides a better view of the cliffs than the heavily visited Pali Overlook. It also turns out to be a pretty neat spot for birdwatching.

The Pali cliffs formed in part because of one of the giant landslides that have originated on the different Hawaiian islands, landslides that carried debris for dozens of miles out to sea, and caused massive tsunamis not seen or experienced in human history. I discussed one of these incredible events in this post.

Dispatches from the Road: Exploring the Ko'olau Caldera

I've always been partial to the Hawaiian Islands that aren't Oahu. I suppose I'm just being snobbish in a geologic way because I feel a visit to the islands is just wasted if all you see is Diamond Head and Waikiki (which is what a great many tourists do). If you want to see a city, well, there are lots of cities all over the world. But there are only a few good-sized Hawaiian Islands. And the scenery on Kaua'i or the Big Island has always seemed to outdo Oahu, to me at least.

But then again, I fool myself into discounting the treasure beneath my feet. The other day I watched the sun rise from Kaiwa Ridge on the Windward coast of Oahu, and had a geological awakening at the same time. The hike is short, just 4/10ths of a mile, but the climb is 600 feet, and I was seriously huffing and puffing most of the way up the small mountain ridge.
My destination was the "Pillbox", a machine-gun emplacement built during World War II. When Pearl Harbor was attacked on Dec. 7, 1941, it was actually the northeast shore near Kailua that was hit first. The concrete structures were soon constructed to defend against a feared Japanese invasion that luckily never came. As I struggled up the steep trail, I found myself imagining the poor Army grunts who had to haul ammunition up these hills.
The view from the top was astounding. I could see the most of the Ko'olau Range, which forms the steep cliffs that surround Kailua and Kane'ohe, as far as Kane'ohe Bay. Hidden in the rocks of these impressive 2,000 foot cliffs was an incredibly violent story that probably affected the entire Pacific Ocean basin.
2.7 million years ago, the Ko'olau volcano was a massive shield complex, much like Mauna Loa or Kilauea today on the Big Island. To the south, the volcano was buttressed against Oahu's other volcano, but to the north there was only deep ocean. A huge caldera, about eight miles long and four miles wide formed the volcanoe's summit. Around two million years ago, the north flank of the volcano destabilized and slipped into the sea, forming an underwater landslide of apocalyptic proportions. The huge mass, called the Nu'unau Slide, flowed underwater for a distance of 120 miles. A single chunk in the mass is eighteen miles long and a mile thick. A slide this large almost surely produced a super-sized tsunami that would have caused serious damage across the Pacific Rim. Needless to say, we wouldn't want it to happen today. Such waves have landed chunks of coral more than a thousand feet above sea level on the islands.
Kaiwa Ridge, the one I hiked the other morning, is made up of dikes and altered basalts of the caldera. The steep cliff in the distance, the Ko'olau Mountains, is the rim of the massive landslide that wreaked havoc across the Pacific. It is on the eroded remnants of this geologic catastrophe that the peaceful village of Kailua is built.

Now this is what I call a vacation!