Unique Places in Okayama-ken

When we stayed at the Ushimado Villa we had a car. The first day we went to the beach and it was fine, but after lunch we decided to take a drive. There are a lot of places to take a walk etc and we parked the car at a car park in the national park (am thinking it was a national park??) and set off to find our own stretch of beach. A little walk thru some bushes, along a path led us to a beautiful spot... no sand, but rocks to bake on and swim off. No-one was around and we could enjoy the rest of the day there.
We did the same on the next day, rather than heading to the beach we drove to a different spot and found a new rock and swam, ate and were merry!