On Kaua'i there is an old sugar plantation with a pretty good-sized irrigation canal through it. To build it they shipped over a bunch of Chinese men from, you guessed it, California. I can’t remember how long it took them to dig through all the hills, but at one point we were under 50ft of rock. The canal goes through five very cool tunnels. The activity is called mountain tubing. Basically, you get on a tube wearing a hard hat with a light, sit back and enjoy the ride. A Kaua’i must!! And no the sugar plantation is no longer in service.
Testing...

The water was brisk baby! But here we go!

Some lady asked us if we were sisters. What?!

In the "play area" they let us get off our tubes.

End of the line.

Huh?!