Since Yakushima is a small island, it only takes about 30 minutes to drive to the country side of the country side... (and there is only left or right direction to explore...). We enjoyed our excursion at Kurio beach where there was a tidal pool, lots of rocks to throw... then a walk through a coral reef beach in the midst of volcanic rocks. Especially loved the way trees were growing over these volcanic rocks. It looked just like a bonsai garden (only in a human scale).
I think three of us were all busy looking for treasures in the coral reef. FB found a beautiful drifted glass sphere in turquoise green... and I picked a few coral reef with amazing textures. We might have to make a box to ship soon.