Scuba Dive a Lava Tube
A lava tube is a natural conduit formed by flowing lava which moves beneath the hardened surface of a lava flow. Tubes can be draining lava from a volcano during an eruption, or can be extinct, meaning the lava flow has ceased and the rock has cooled and left a long cave. There are several places to scuba dive these tunnels in Hawaii. This is not for the amateur diver so make sure you have some cave diving experience before attempting this kind of a dive. If the underwater adventure is a little outside your comfort zone, you can go on a mini spelunking adventure above water through pathways where hot lava once flowed into the sea.