Who's afraid of the dark? Test yourself at the end of this underground walk by flipping off your flashlight. Eerie! One of the odder sights on the Road to Hana, this mammoth cave was formed by ancient lava flows. The lave tube is so large that it once served as a slaughterhouse – 17,000lb of cow bones had to be removed before it was opened to visitors!
Winding your way through the extensive cave, which reaches heights of up to 40ft, you’ll find a unique ecosystem of dripping stalactites and stalagmites. The journey is well signed, takes about 45 minutes, and is a perfect rainy-day activity. Admission includes flashlights and hard hats. If you want to lose the kids, an adjoining botanical maze made from red ti plants is free. Hana Lava Tube is half a mile from the Hana Hwy.