We spent a day driving and walking through the amazing Hawaii Volcanoes National Park, and saw so. much. lava (duh!). No, seriously, we were floored by the size of the fields of hard black rocks. And even though we didn't get to see any actual flowing lava up close, seeing the ripples in the rock formations, how they covered roads and trees, and being able to look into old craters and ancient lava tubes gave us an incredible insight in the crazy world of volcanoes.
We also drove back into the park after sunset and got to see the glow emanating from an active crater of the Kilauea volcano. Realising that the hot bubbling liquid that was jumping up and down in front of our very eyes is what the whole centre of our earth is made out of was a rather humbling thing.