Lava tubes are formed naturally when hot lava flows down a naturally-existing canyon or gorge. The lava forms a crust on top, which eventually thickens around the sides until a nearly-circular channel is left in the center. This channel carries lava until the volcano stops producing it. The last of the lava drains out, leaving a long cave-like channel. Hawaii is full of them.
Since many of the irrigation channels on Kauai are now unused, some entrepreneurs leased the rights to use one that is on private property for tourism. It runs for miles, passing through four pitch-dark lava tubes on the way.
When we arrived at the office, we were issued helmets with headlamps, and a pair of gloves to protect us from the abrasive lava rock that forms the lava tubes. Then, we boarded Swedish-army troop transport trucks for the ride to the irrigation channel.
We drove on dirt roads that seemed like they were in the middle of the Serengeti.
Along the way, we were treated to the company of this member of the staff, who has the worst case of ADD in Hawaii.
We arrived at our destination, which was technically the middle of nowhere.
This is the channel that was going to carry us through the wilderness.
Mr. ADD gave us a lecture on safety, assuring us that there were no leeches, piranhas or alligators in Hawaii. He then warned us not to pee in the channel, although he did not specify why.
And then we got into large inner tubes for the trip. Parts of it were quiet and scenic, and other parts were fast and exciting.
The lava tubes were dark and mysterious phenomena. One of them was over a mile long. You could see where the tubing staff had driven metal anchors into the ceiling to hold metal mesh, so that chunks of lava rock don’t fall onto the tourists.
If you are interested, here is a movie of the experience, edited down from over an hour to just over four minutes.
After the trip, we had lunch at a scenic spot.
I know it probably doesn’t sound like that much fun, but it was surprisingly enjoyable, ranking high on our list of favorite activities in Hawaii.