Ronu Kau Volcanic Crater

One mile in diameter, the vast crater that was once a volcano is a breathtaking site. Not only wide, it is also deep—it dips so low, it has its own microclimate at its base, which filled with reeds and water. The lip where the lava flowed into the sea is still apparent and makes a dramatic view even more spectacular. No one is quite sure how deep the water goes, but when the island suffered a recent drought, locals washed their clothes in the lake.